IntroductionAs one of today’s busy Federal facility or energymanagers, you may be seeking ways to solve prob-lems such as high energy costs or low electric powerreliability at your facility. If so, distributed energyresources (DER) could be the solution you’re looking for.

What are distributed energy resources?Distributed energy resources are small, modular,energy generation and storage technologies thatprovide electric capacity or energy where you needit. Typically producing less than 10 megawatts(MW) of power, DER systems can usually be sizedto meet your particular needs and installed on site.

DER systems may be either connected to the localelectric power grid or isolated from the grid instand-alone applications. DER technologies include

wind turbines, photovoltaics(PV), fuel cells, microturbines,reciprocating engines,

combustion turbines, cogeneration, and energy storage systems.

How are DER systems used?DER systems can be used in several ways. They canhelp you manage energy bills and ensure reliablepower by augmenting your current energy services.DER systems also enable a facility to operate inde-pendently of the electric power grid, whether bychoice or out of necessity. Certain DER systems caneven lower emissions and improve fuel utilizationon site.

Utilities can use DER technologies to delay, reduce,or even eliminate the need to obtain additionalpower generation, transmission, and distributionequipment and infrastructure. At the same time,DER systems can provide voltage support andenhance local reliability.

How do I know if DER systems are the rightchoice for my facility?Today, several economic and environmental factorsmake it worthwhile to consider DER. These factorsinclude the high prices associated with both electricenergy and fuel in recent years. Uncertain fuel sup-plies and the increasing potential for disruptions in electricity service are prompting Federal man-agers to look for alternatives to traditional energyproviders and for new ways to supplement currentsupplies.

Particularly where a facility’s energy-producinginfrastructure is aging, it may be time to review current operating costs and maintenance require-ments. The performance, cost, and availability ofDER technologies have all been improving steadilyover the past several years. New technologies aremuch more efficient than old ones, so a replacement

or upgrade may pay for itself soonerthan expected. Also, energy security is a primary concern at many Federalfacilities. In those cases, DER systemscan power mission-critical loads, reducehazardous or costly power outages, anddiversify the local energy supply.

Military facility energy managers, however, may want to consider the likelihood of privatization in deciding

Using Distributed Energy Resources A How-To Guide for Federal Facility Managers

F E D E R A L E N E R G Y M A N A G E M E N T P R O G R A M

DistributedEnergyResources:A How-ToGuide

U.S. Departmentof Energy

Office of EnergyEfficiency andRenewable Energy

Internet: www.eren.doe.gov/femp/

DER systems are made up of manydifferent power-generating technologies.

Wind systems

Energy storagesystems

Fuel cells

Solarsystems

Microturbines

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whether to invest in a DER system. If the facility's utility infrastructure couldsoon be sold to a private entity, it mightnot make economic sense to invest in a new DER system that would be unacceptable to a potential buyer. But inthe right circumstances, even militaryfacilities can benefit from using DER.

What is the purpose of this guide?The Department of Energy’s (DOE’s)Federal Energy Management Program(FEMP) has established the DistributedEnergy Resources Program to assistFederal agencies in implementing DERprojects at their facilities. FEMP pre-pared this How-To Guide to assist facilitymanagers in evaluating potential appli-cations and benefits. The guide also pro-vides practical, step-by-step advice onhow to carry out a Federal DER project.It describes and explains—

• DER applications, and the potentialbenefits of using DER in Federal facilities

• DER technologies, and how to matchthem to applications

• A step-by-step approach to imple-menting projects

• Barriers that you may encounter, andhow to overcome them

• Resources that can assist you inimplementing new DER projects.

We hope this guide helps to make yourDER projects a success.

Seven Steps to SuccessHow do you, as an energy or facilitymanager, determine whether DER willmake sense for your facility’s energyneeds? And if so, which technology orsystem is the best? Finally, what is theprocess you need to follow to get a DER project financed, designed,installed, and operating?

Before even considering DER, make sure you have taken advantage of all the energy-saving measures that areavailable and applicable to your facility.These include using highly efficientinsulation, lighting, and heating, venti-lation, and air-conditioning (HVAC), as

well as passive solar design and othereffective techniques. (See FEMP’s Website, www.eren.doe.gov/femp/, formore information about energy-efficientfacilities.) The more you can reduce yourenergy requirements, the smaller youcan size the DER system you will beinstalling. Here are seven steps you canfollow to obtain a DER system that’sright for you.

STEP 1: Analyze YourFacility's Energy NeedsIn this step, you can determine whatyour facility’s energy needs are, whatproblems you need to solve, and whatbenefits can be gained by using DERsystems. This list of basic DER applica-tions will help you determine which oneor ones apply to your facility. It will alsohelp you choose appropriate DER tech-nologies in Step Two.

• Standby Power. Problem: Your powersupplier has an unacceptably highincidence of service interruptions, ortakes a long time to restore serviceafter an interruption. This is calledlow reliability, and the result is a shut-down in operations until power isrestored. Solution: Install a DER sys-tem that can meet your power needswhen service is interrupted, to servecritical loads until service is restored.Benefits: Highly reliable operation,minimal down time.

• Low-Cost Energy. Problem: Yourenergy supplier has high rates.Solution: Install a DER system to gen-erate some or all of your facility’spower using renewable technologies,or change to more efficient and clean-er sources of fossil fuel generation.Benefit: Lower energy bills.

• Stand-Alone Systems. Problem: Yourfacility needs electric energy, but it is in a location that can’t be servedeconomically by traditional utilities.Solution: Install a DER system to gen-erate power dedicated solely to off-grid loads. Benefits: Independentoperation, cost savings.

• Combined Heat and Power (CHP, orCogeneration). Problem: Your facility

needs electric energy, but it also hasother energy needs, for example, toheat or cool water or interior spaces.Solution: Install a DER system to generate power and use the wasteheat for auxiliary processes thatwould otherwise require fuel.Benefits: Substantially greater efficiency, lower energy costs and fuelrequirements, and fewer air emis-sions, in many cases. (See p. 6,Table 2, for more information.)

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STEP 4:Acquire resources

and assistance

STEP 3:Screen the

technologies

STEP 2:Select DER

technologies

STEP 1:Analyze yourenergy needs

STEP 5:Develop a

project plan

STEP 6:Address potential

barriers

STEP 7:Install and operateyour DER system

Following these seven steps will help youimplement a successful DER project.

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• Peak Shaving. Problem: Your powersupplier bills you a monthly chargebased on your highest peak usagerate, even if it’s only a few hours eachmonth. Solution: Install a DER to provide power during times of peakusage to lower demand charges.Benefit: Lower monthly utility bills.

• Improved Power Quality (PQ).Problem: The power provided to yourfacility by your energy supplier is not electrically "clean" or constant,causing problems with your facility’sequipment (see page 8 for details).Solution: Install a DER systemdesigned to mitigate the particularpower quality symptoms you areexperiencing. For example, frequentmomentary outages can be effectivelyaddressed with an uninterruptiblepower supply (UPS) system or a dis-tributed storage device. Benefits:Obtain cleaner power, ride throughmomentary outages, protect delicateequipment.

• “Green” Power. Problem: Your facilityis in an environmentally sensitivearea. Solution: Install low- or zero-emission DER systems that generateenvironmentally preferable power,such as wind turbines, photovoltaics,fuel cells, or CHP systems. Replacingold power generation equipmentwith cleaner, more efficient DER tech-nologies may also reduce emissions.Benefits: Easier emissions permitting,minimal environmental impacts.

STEP 2: Select a DERTechnology In this step, you can evaluate today’sDER technologies, selecting the onesthat meet your needs. Table 1 on pp. 4and 5 shows which technologies aresuitable for various DER applications.Refer to the table as you weigh the prosand cons of the candidate technologies.

DER systems can be made up of one ormore primary technologies—such asinternal combustion engines, combus-tion turbines, fuel cells, photovoltaics,wind turbines, and batteries—alongwith supporting technologies—such as power conditioning equipment,

controls, communications, fuelhandling and storage systems,CHP systems, and emission con-trols. You will also want to weighimportant environmental andfuel-use issues.

What are the technologies?Many combinations of technolo-gies and fuel options are possible,to take advantage of the way indi-vidual technologies complementeach other and to make them asrobust and cost-effective as possi-ble. See Table 2 for comparativecost and performance informationabout today’s DER technologies, whichinclude the following:

• Diesel Engine generator sets(gensets) consist of a diesel-cycle(compression ignition) reciprocatingengine prime mover coupled to anelectric generator. The diesel engineoperates at a relatively high compres-sion ratio and relatively low rpm.Diesel engine gensets are a proven,cost-effective, extremely reliable andwidely used technology. They aremanufactured in a wide range ofsizes, from about 1 kilowatt (kW) upto about 10 MW. They can be cycledfrequently to operate as peak-loadpower plants or as load-followingplants; they can also be run in base-load mode in off-grid systems. Majordrawbacks include very high levels ofemissions (particularly nitrogen oxides,a major component of smog), and theneed for sound attenuation to mufflethe loud engine noise. Diesel enginesare thus probably not suitable formost Federal facilities, and should beconsidered only if other technologiesare not practical. One of the leastexpensive DER technologies, theycost about $810/kW, installed.

• Dual-Fuel Engine gensets consist of a diesel-cycle engine modified to usea mixture of natural gas and dieselfuel (typically, 5% to 10% diesel byvolume) connected to an electric gen-erator. The small amount of dieselfuel allows the use of compressionignition, and the high percentage ofnatural gas in the mix results in much

lower emissions (and somewhatlower power output) than those of a diesel engine. In most other costand operational respects, dual-fuelengines are comparable to diesels;they are available in sizes from a few kilowatts to about 10 MW at aninstalled cost of about $875/kW.

• Natural Gas Engine gensets are madeup of a reciprocating (piston-driven)natural gas-fueled engine using aspark-ignition system (Otto fuelcycle) coupled to an electric genera-tor. In most other respects, naturalgas engines perform similarly todiesels and dual-fuel engines, buthave the potential for the lowestemissions of all types of reciprocatingengines. They are available in sizesfrom a few kilowatts to about 5 MW,and they cost about the same as dieseland dual-fuel engines—around$825/kW.

• Combustion Turbines (also calledgas turbines) burn gas or liquid fuel;hot gases expand against the bladesof a rotating shaft, producing a high-speed rotary motion that drivesan electric generator. While they maytake a few more minutes to get up tospeed in comparison to reciprocatingengines, gas turbines are well suitedfor peaking and load-following appli-cations and for baseload operation inlarger sizes. Installed costs are some-what higher than those of reciprocat-ing engines, and maintenance costsare slightly lower. Turbines are effi-cient and relatively clean. They can

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Matching DER Technologies to Your ApplicationsWhen using this chart to select a technology for a specific application, you will also want to consider such key factors ascommercial readiness, economics, availability, and environmental considerations before making your selection. Thediscussion that follows should provide some additional guidance in selecting the technologies.

Table 1. DER Technology Applications Matrix

Technology Application

Standby Low-cost Stand- Combined Peak PowerPower Energy alone Heat & Shaving Quality

System Power

Diesel Engine ✓ ✓ ✓ ✓ ✓

Natural Gas Engine ✓ ✓ ✓ ✓ ✓

Dual Fuel Engine ✓ ✓ ✓ ✓ ✓

Microturbine ✓ ✓ ✓ ✓

Combustion Turbine ✓ ✓ ✓ ✓ ✓

Fuel Cell (1) ✓ ✓

Photovoltaics (1) ✓ ✓

Wind Turbine (1) ✓

Uninterruptible Power Supply (UPS) ✓ ✓

Battery System ✓ ✓

Flywheel ✓ ✓

Superconducting Magnetic Energy ✓Storage (SMES)

Hybrid Systems (2) ✓ ✓ ✓ ✓ ✓ ✓

(1) Although fuel cells, photovoltaics, and wind turbines may not offer the lowest cost power option, their low environmental impacts greatly enhance the value of the power they provide.

(2) Hybrid systems are any combination of the technologies listed above.

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Standby Power. To acquire the most economical DERpower-generating system to use when the utility supply isdown, you should first estimate how often the DER willhave to start up and how many hours per year it will haveto operate. For standby power applications, fuel andmaintenance costs will be low because outages usuallyoccur only a few hours per year; consequently, capitalcosts should be low. Diesel engines are likely to be theleast expensive option, but they can present environmental challenges. Natural gas and dual-fuel enginesmay be more environmentally acceptable than diesels.Microturbines can be a good choice for small applications(less than 100 kW); combustion turbines can be good forlarger applications, where natural gas is available andemissions are a concern. UPS systems are well suited toapplications where outages last less than about 15 min-utes. Batteries can handle applications of a few kW foroutages of about 1 to 2 hours. Hybrid technologies, which

combine generation and storage technologies for specificapplications, have many benefits and may be best if youneed fuel redundancy, expect a wide range in duration ofoutages, or have multiple applications.

Low-Cost Energy. If low-cost fuel is available, or electricrates are high in your area, or both, you may be able toreduce your utility bill by generating some or all of yourown power. Diesel, dual-fuel, and natural gas enginesare the least expensive to purchase, but emissions andmaintenance costs should be considered when the num-ber of operating hours is high. Combustion turbines arepreferred for large applications; they have lower mainte-nance costs and much lower emissions than reciprocat-ing engines. Microturbines, which are relatively lower inefficiency and have higher capital costs, are probably notas cost-effective. Photovoltaics, although high in cost ini-tially, often make sense in the long term, especially if the

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local utility has established net metering rules (see belowfor more information). Wind turbines are less expensivethan PV arrays, but may not qualify for net metering.However, in areas with high average wind speeds, turbines can provide a substantial amount of energy.Hybrid systems—such as PV or wind with batteries—aremore expensive but work over a broader range of fuelcosts and applications than single technologies. In addi-tion, using the waste heat generated by some DER technologies to produce both heat and power on site can reduce overall energy costs.

Stand-Alone Systems. A DER in this application will run around the clock and constantly match its output tothe demand. Therefore, high efficiency is required to minimize fuel costs and emissions. Maintenance costsare also an important factor, and reliability is paramount.Engines and combustion turbines are often the first choices in terms of capital cost. Engines and microtur-bines are usually preferable for smaller applications; combustion turbines are preferable for larger applica-tions. Fuel cells are the most expensive to install butdesirable from an environmental perspective. PV, windturbines, and hybrid systems are beneficial in areas with-out adequate supplies of fossil fuels or where environ-mental permitting is difficult, and in off-grid applicationswhere grid extensions are very expensive. Particularly in remote, off-grid areas, the cost of operating and main-taining fossil-fuel-fired engine gensets is significant. Thecost of transporting and storing fuel, combined with thepotential for fuel spills and subsequent cleanup, canmake hybrid renewable energy systems much more life-cycle cost-effective than fossil gensets alone.

Combined Heat and Power (CHP). Only the power-generation technologies that produce excess heat can beused for CHP applications; these include engines, com-bustion turbines, fuel cells, and microturbines. Additionalequipment must be installed to capture the heat and useit in the secondary process, at an average additional costof $400/kW. Engines and turbines (including some micro-turbines) have been used for CHP applications. Any DER

technology that can produce waste heat can be used in aCHP application with greater overall system efficiencies(because of the higher fuel utilization efficiency) and per-haps better economics. (See page 9 for more informa-tion. You can also use the CHP Online Calculator—seeResources on p. 16 —to determine whether CHP is cost-effective for your needs.)

Peak Shaving. DER systems can generate power duringthe times when purchasing energy from the utility wouldbe very expensive. These include peak demand hours,when time-of-use rates are in effect, and hours when utili-ties are capacity-constrained. Utilities often assessdemand charges—monthly charges based on highestpeak usage—for commercial customers. Using DER tolimit peak usage will help you avoid these costs. The sys-tem may run 200 to 2000 hours per year, so you shouldconsider the trade-off between installation costs and effi-ciency to select an appropriate DER technology. Enginesand hybrids are likely to be preferable for small applica-tions at lower run times, and turbines for larger applica-tions at higher run times. PV systems can provide peakshaving in facilities where the greatest requirement forenergy occurs when the solar resource is at its highestintensity, such as for air-conditioning in commercial build-ings. For these applications, PV systems have excellentload-matching characteristics.

Power Quality. Any DER prime mover technology can beused to provide dedicated, high-quality power to highlysensitive or mission-critical loads and to eliminate down-time. For small applications and brief power outages, aUPS is likely to be the most economical choice. For volt-age sags, spikes, noise, and other random PQ anom-alies, preferred technologies include batteries, flywheels,and SMES. They can be operated in a constantly-onmode, filtering out unwanted qualities of the power signal.Adding higher quality electronics and energy storage sys-tems can improve the power quality of any prime movertechnology. See page 8 for more information about powerquality.

Net MeteringNet metering measures the difference between the electricity you buy from your utility and the electricity you produceusing your own generating equipment. Your electric meter keeps track of this "net" difference as you generate electricityand take electricity from the grid. Your utility or electric service provider bills you for the “net” energy you use (if any) ona monthly or yearly basis, depending on the program. Net metering allows you to get full retail value for most, if not all,of the electricity you produce. Any excess electricity you generate goes back into the electric grid and essentially creditsfuture energy use. Getting this high retail value for your excess electricity makes owning your own generating systemmore cost-effective. Net metering programs have been enacted in 35 states. Although specific requirements vary signif-icantly from state to state, many programs allow net metering for residential and commercial customers, with systemsize limits of 10–100 kW. Check with your state’s public utility commission for the specific rules that could apply to you.

For a summary of state net metering programs, see www.eren.doe.gov/greenpower/netmetering.

easily be fitted with pollution con-trols to run even cleaner. They areavailable in sizes ranging from about 300 kW to several hundredmegawatts, and costs range from$910/kW to $1,400/kW, installed.

• Microturbines are smaller, somewhatless efficient versions of combustionturbines, in the range of about 30 to250 kW. They run on natural gas athigh speeds (typically around90,000 rpm). The electrical output ofthe generator is typically passedthrough an inverter (an electronics-based power converter, also called apower conditioning unit or PCU) toprovide 60 Hz AC power. Micro-turbines targeted to the small indus-trial and commercial market aredesigned to be compact, affordable,reliable, modular and simple to

install. The newest versions meetvery low emissions requirements.Microturbines are commerciallyavailable and currently cost around$1,000/kW.

• Fuel Cells produce DC electricity by a thermochemical process in whichhydrogen (H2) is passed over ananode and air over a cathode in anelectrolyte bath; the DC power isinverted to AC for grid operation. By-products are heat, water, and carbondioxide, making fuel cells one of thecleanest sources of energy. Unless it istransported to the site, the hydrogencomes from reforming a fuel such asnatural gas or propane, a process thatmay produce environmental emis-sions. Fuel cells using a phosphoricacid electrolyte were the first tobecome commercially available; solid

oxide, molten carbonate, and protonexchange membrane (PEM) technolo-gies are poised to follow. Fuel cellsare efficient, quiet, and modular.

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Microturbines can be powered by natural gasor biofuels to provide a reliable source ofpower.

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Table 2. Summary of Cost and Performance Parameters for Distributed Generation Technologies

Technology Size Range Installed Cost Heat Rate Approx. Variable Emissions (1)(kW) ($/kW) (Btu/kWhe) Efficiency O&M (lb/kWh)

(2) (%) ($/kWh) NOx CO2

Diesel Engine 1–10,000 350–800 7,800 45 0.025 0.017 1.7

Natural Gas Engine 1–5,000 450–1,100 9,700 35 0.025 0.0059 0.97

Natural Gas Engine w/CHP (3) 1–5,000 575–1,225 9,700 35 0.027 0.0059 0.97

Dual-Fuel Engine 1–10,000 625–1,000 9,200 37 0.023 0.01 1.2

Microturbine 15–60 950–1,700 12,200 28 0.014 0.00049 1.19

Microturbine w/CHP (3) 15–60 1,100–1,850 12,200 28 0.014 0.00049 1.19

Combustion Turbine 300–10,000 550–1,700 11,000 31 0.024 0.0012 1.15

Combustion Turbine w/CHP (3) 300–10,000 700–2,100 11,000 31 0.024 0.0012 1.15

Fuel Cell 100–250 5,500+ 6,850 50 0.01–0.05 0.000015 0.85

Photovoltaics 0.01–8 8,000–13,000 -- N/A 0.002 0.0 0.0

Wind Turbine 0.2–5,000 1,000–3,000 -- N/A 0.010 0.0 0.0

Battery 1–1,000 1,100–1,300 -- 70 0.010 (4) (4)

Flywheel 2–1,600 400 -- 70 0.004 (4) (4)

SMES 750–5,000 600 -- 70 0.020 (4) (4)

Hybrid Systems 1–10,000 (6) (5) (5) (5) (5) (5)

(1) Nationwide utility averages for emissions from generating plants are 0.0035 lb/kWh of NOx and 1.32 lb/kWh of CO2.(2) The high end of the range indicates costs with NOx controls for the most severe emissions limits (internal combustion technologies only).(3) Although the electric conversion efficiency of the prime mover does not change, CHP significantly improves the fuel utilization

efficiency of a DER system.(4) Storage devices have virtually no emissions at the point of use. However, the emissions associated with the production of the

stored energy will be those from the generation source.(5) Same as generation technology selected.(6) Add cost of component technologies.

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They are available in sizes rangingfrom a few watts to 200 kW—the cur-rent commercially available size forstationary power applications.Although costs are expected to godown, fuel cells are now one of themost expensive DER technologies,starting at about $5,500/kW,installed. FEMP’s Federal TechnologyAlert on fuel cells (see Resources,p. 16) provides more information.

• Photovoltaic Cells are thin layers of a semiconductor (usually crystallinesilicon) that convert sunlight directlyto DC electricity; an inverter convertsthe DC to standard AC power forconnection to utility systems. These“solar cells” are built up into panelswith power ratings ranging from afew watts to about 100 W. The panelsare modular and can be configuredinto larger arrays to match almostany load requirement. Noise andemissions are nonexistent, and main-tenance is minimal because there areno moving parts. Photovoltaic sys-tems are a proven technology and are available from numerous manu-facturers. Depending on the applica-tion, PV systems can range from$8,000/kW to $13,000/kW, installed.Grid-connected systems typically fallin the low end of the range, while sys-tems with battery storage constitutethe high end.

• Wind Turbines, another renewableenergy technology, contain propeller-like blades that turn the energy in thewind into rotational motion to drive a generator. Most wind turbines areasynchronous, meaning they turn atvariable speeds; the output of thegenerator must pass through aninverter to achieve 60 Hz AC electrici-ty. Wind turbines range in electricaloutput from a few watts to more than1 MW. Applications include remotepower systems, small-scale or resi-dential electricity production, andutility-scale power generation. DER-scale systems can cost anywhere from$1,000/kW to $3,000/kW installed,depending on the application. Likephotovoltaics, wind turbines are a

proven technology and are availablefrom several manufacturers.

• Storage Devices take energy from theelectric grid or another source (suchas a renewable DER) and store it,making it available when needed.Storage technologies currently avail-able have a range of characteristicsfor various applications. Batteries arethe most common form of electricenergy storage; applications rangefrom low-power uses, such as remotetelecommunications, to high-poweruses, such as utility grid support(requiring an inverter). A UPS isanother common storage system, typ-ically consisting of batteries mated tocontrol electronics that convert storedenergy to AC electricity and dispatchit as needed (for example, to providefull power during an outage or tosmooth out power quality problems).Flywheels convert electric or mechani-cal energy into rotational energy andinvert it for use when needed.Superconducting magnetic energystorage (SMES) uses a magnetic coilcooled to very low temperatures tostore electric energy with little loss;like other DC devices, it uses aninverter to convert DC to AC that can be dispatched to a utility grid.These storage technologies are allcommercially available and becomingmore cost-effective as applicationsincrease. The cost of purchasing andinstalling energy storage systems canrange from $1,100/kW to $1,300/kW.

• Hybrid Systems are combinations of these technologies, designed forspecific or unusual applications.Renewable energy technologies suchas wind and solar systems, for exam-ple, depend on energy sources thatcannot be dispatched—i.e., we haveno control over their availability. For this reason, it can be necessary to combine them in a hybrid system,such as a PV system with batterybackup, to collect energy for usewhen a facility needs it. Nonrenew-able hybrid DER systems are alsoused; one example is a battery systempackaged with a microturbine, to ridethrough short outages with the bat-teries and use backup power from themicroturbine for sustained outages.

Depending on your needs, more thanone of these technologies and systemsmight work for you. In that case, you could custom-design several technologies and control systems toobtain the greatest benefit.

What are the environmental issues?An important consideration in choosinga DER technology is the environmentalimpact associated with it. Certain DERsystems can have a positive impact onair emissions, particularly NOx and SOx,which are by-products of fossil fuel com-bustion and key constituents of smog.Table 2 shows output levels of the key

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Power Quality The power generated by an electric utility starts outas a “clean” 60 Hz sine wave (Fig. 1), but both utilityand customer equipment can affect the pureness(quality) of the power delivered to the user. Loadand generation changes, equipment switching, andelectronically controlled loads can all cause signifi-cant disturbances to the electrical waveform. Poorpower quality can be merely annoying or it canadversely affect or damage sensitive loads such ascomputers, adjustable-speed drives, and motors,disrupting important facility processes.

Symptoms of poor PQ include the following:

Voltage sags and swells — the voltage is too high ortoo low for a period of several cycles to several min-utes (Fig.2).

Voltage spikes — sharp, randomly occurring pulsesin the voltage (Fig. 3).

Momentary outage — complete interruption ofpower for up to 5 minutes (Fig. 4).

Harmonic distortion — variation from a pure sinewave due to harmonic frequencies (Fig. 5).

Other signs of poor PQ are variations in the frequen-cy from a constant 60 Hz, noise (low-level randomvoltage variations), and unbalanced voltages andcurrents between the three phases of the electricsystem.

How do you know if you've got PQ problems? Youmay see lights flicker or go dim or bright. Motors canvibrate, make noise, overheat, or stall. Outages areeasy: everything goes black. Some symptoms arehard to detect, so you might want to ask your localutility or a consultant to monitor your power and do a PQ analysis for you.

If your facility has experienced any of these symp-toms, first ask your local utility or vendors about thesolutions they could provide. In many cases,improper grounding or problems inside your facilitymay be to blame; sometimes nearby customers arethe source of the problem. Because many utilitiesmake no warranties concerning power quality, youmay need to consider installing PQ mitigation tech-nologies. These include UPS, battery systems, stor-age technologies, motor-generator sets, isolationtransformers, voltage regulators, line conditioners,filters, shielding and grounding techniques, andsurge suppressors.

Figure 1: Normal Power Waveform

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Figure 2. Voltage Sags and Swells

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Figure 3. Voltage Spikes

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regulated emissions of DER technolo-gies, CO2 and NOx; SOx emissions arenegligible for most DER technologies,since the fuel used is typically naturalgas. Note that the units employed arepounds per kilowatt-hour (lb/kWh);this is an example of an output-basedstandard, which relates emissions levelsto the efficiency of the technology, andallows technologies to be compared on a consistent basis. Sometimes emissionsmeasurements are given in terms ofinput (e.g., pounds of pollutant per mil-lion Btu of fuel input) or on the basis of concentration (parts per million, orppm). These measures do not clearlylink actual emissions to the amount ofproduct (in this case, kWh of energy),making it difficult to determine whichtechnologies are the cleanest.

Table 2 lists the heat rates of the tech-nologies in terms of Btu/kWh, repre-senting the amount of fuel inputrequired per kilowatt-hour of electricaloutput produced. This can help youevaluate the fuel requirements of a DERfor a given output and hours of opera-tion, as well as output-based emissionsin lb/kWh, so you can choose the cleanest feasible technology for yourfacility. Note that renewable energy sys-tems and fuel cells have virtually no airemissions. Because overall system effi-ciencies are higher, CHP systems alsohave lower emissions than DER systemsthat do not utilize waste heat.

Keep in mind that any energy your facil-ity generates usually displaces energypreviously generated by some othersource, so net emissions are a key con-sideration. For example, if you install awind turbine, all the air emissions fromthe usual generation source (e.g., thelocal utility), will be avoided for eachkWh of energy the wind turbine pro-duces. On the other hand, if you install adiesel engine, then it is possible that netemissions will be greater, becausediesels have higher levels of some keyemissions on a per-unit basis than mostconventional utility generation methods.Table 2 shows the average emissions forU.S. utility generation, which is a mix of fossil fuel (coal, oil, and natural gas),

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Combined Heat and PowerMany types of distributed generation can provide useful and valuable thermalenergy by capturing excess heat energy produced during electricity genera-tion and using it to heat or cool water or interior space. The excess heat canalso be used as energy input to an industrial process, in lieu of burning fuel.This energy capture and reuse process is known as combined heat andpower, CHP, or cogeneration.

Some energy users require substantial amounts of heat, especially for indus-trial, institutional and agricultural operations. In those cases, CHP can saveenough on fuel costs to substantially improve the overall economics of DERinstallations.

Federal facilities that are likely to benefit the most from CHP applicationsinclude hospitals, prisons, R&D facilities, and industrial buildings.

Assuming that the combustion of fuel to produce heat (usually in a boiler) istypically up to 85% efficient, each Btu of heat captured from the distributedgenerator in a CHP process offsets the need to burn about 1.18 Btu of fuel.The incremental project cost for CHP is highly site-specific, but generallyabout $400/kW. This represents the estimated costs for piping, heat exchang-ers, and engineering associated with installing CHP. CHP system integrationcan sometimes be simplified at facilities that already have a central plant or a large mechanical room, thereby reducing costs. And any site with a steamplant that runs at moderate to high pressures might be able to use back-pressure steam turbines to generate electricity cost-effectively.

CHP can also have substantial environmental benefits by reducing air emis-sions from boilers or other processes that require heat input. This fact may be helpful in obtaining permits from local air regulatory authorities. Nominalvalues for avoidable boiler emissions are shown in the table below. They arebased on the leading data source for this kind of information, the U.S.Environmental Protection Agency. In addition to nitrogen oxides and carbondioxide (NOX and CO2), boiler emissions can also include sulfur oxides(SOX), carbon monoxide (CO), volatile organic compounds (VOCs) and par-ticulate matter (PM). (Values shown in Table 3 are representative of boilerscurrently in use that are the most likely candidates for replacement by CHP,so they are somewhat higher than values for newer, more efficient boilers.)

Table 3. Avoided Boiler Air Emissions for CHP Operation(pounds per million Btu)

NOX SOX CO CO2 VOC PM

Nominal 0.14706 0.00059 0.0824 118 0.00539 0.00745

Best Reported 0.03137 0.0235

Poorest Reported 0.2745 0.0961

FEMP offers free CHP screenings; please contact your DOE Regional Office representative for more information (see Resources on p. 16). And seeOak Ridge National Laboratory’s online CHP evaluator: www.eren.doe.gov/der/chp/chp-eval.html.

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hydropower, nuclear, geothermal, and a few other sources.

Noise will also be a consideration inchoosing a DER technology, because ofthe proximity of the system to homesand businesses. Most urban and subur-ban areas have noise ordinances, so mufflers or other sound attenuationmethods may be necessary. In addition,visual and aesthetic impacts are some-times a concern, requiring landscaping,enclosures, or other measures.

What fuels should be used?Availability, price, and storage are thekey concerns regarding the fuel used to power your DER system.

Diesel fuel is readily available at a reasonable cost; however, it requires an on-site storage tank and periodic deliveries, and spills or fumes arealways possible.

Biodiesel fuel can be an alternative fordiesel engine generator sets in areaswhere it’s available. Biodiesel is madeby reacting natural oils and fats with analcohol. It is generally distributed as a20% blend with number 1 or 2 dieselfuel. Biodiesel can significantly reduceCO2, SO2, and particulate matter emis-sions, but it may increase NOx in somecases.

Natural gas is a cleaner alternative todiesel, and it is comparable in terms ofoverall cost. In areas where gas utilitieshave pipelines, a gas line extension maybe required, at additional cost, but astorage tank is not needed. If it isimpractical or prohibitively expensive to run a gas line, you may need gasdelivery and a storage tank. Propane isanother alternative to diesel fuel, wherenatural gas is not available. Natural gasand propane may or may not be cleaneralternatives to biodiesel; it depends onthe application.

Biomass—plant matter such as trees,grasses, agricultural crops or other bio-logical material—can also be used inplace of some fossil fuels. The most com-mon forms of biomass used to generateelectricity are the residues from the food,fiber, and forest product industries. Butmunicipal solid waste facilities andsewage treatment plants can also pro-duce fuel to power DER technologies.

PV systems depend on the availabilityof sufficient sunlight in a given area. Bypaying careful attention to the designand placement of the solar panels, andadding energy storage batteries (typical-ly, the deep discharge type), you canmaximize the potential of your solarinstallation.

Wind energy is also highly dependenton location, especially on the averagewind speed in a given locale and thedaily and seasonal variations in windspeed. Again, adding storage can pay off in terms of the overall functionalityof a wind system.

Hybrid systems, such as wind or PVplus storage and a small diesel backupgenerator, may be necessary and cost-effective in situations where high relia-bility and/or stand-alone operations are required.

STEP 3: Screen theTechnologiesAt this point, it is a good idea to performa screening exercise to eliminate DERcandidates that are not really practical or feasible for your facility. This helpsyou make sure that there are no

“showstoppers” to derail your project,and that the economics of your choicesare favorable.

For example, if natural gas is not avail-able at your facility, a technology thatrequires it is clearly not the right choice.If air emissions are strictly controlled inyour area, diesel engines would not beacceptable, either, and other fossil fueltechnologies may be problematic, aswell. Be sure your choices do not stopthe show in terms of making your project a success.

You can also look at the barriers in Step 6to see if any of them would categoricallyrule out any of the DER options youhave selected. Then, you’ll want to conduct an economic evaluation.

Some people balk at the high first costsof certain DER technologies, such as fuelcells and PV systems. Researchers arestill working on ways to reduce these initial costs to more competitive levels.However, many DER technologies arelife-cycle cost-effective in certain appli-cations right now.

Federal facilities are required to performlife-cycle cost assessments on all plan-ned energy projects, because these assess-ments take into account the benefits of aproject over its entire operational life.For example, a PV system has a highercapital cost than a similarly sized natu-ral gas engine. But the PV system doesnot use fuel and can last up to 20 yearsor more. The natural gas engine, in con-trast, will use a lot of fuel during its life-time, which may only be a few years.

You can evaluate the cost-effectivenessof a DER system by comparing the life-cycle costs of your current energy usagescenario to the scenario in which a DER system is designed, installed, and operated.

To simplify this process, DOE provides a Building Life Cycle Cost (BLCC) economic analysis software tool, whichis used to analyze the life-cycle cost-effectiveness of energy technologies(including DER) in an integrated facilityenvironment. See Resources on p. 16 formore information on BLCC and how touse it.

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Electrical Output: AC vs. DCVirtually all electric systems incommon use in North Americatoday are 60 Hz alternating current(AC) systems. Some DER tech-nologies—like engines and com-bustion turbines—produce ACpower directly and can be connect-ed to the electric grid or AC loadsin a straightforward manner. Othertechnologies—like fuel cells, pho-tovoltaics, and wind turbines—pro-duce direct current (DC) power,which must be passed through apower electronics device, called aninverter or power-conditioning unit,to produce 60 Hz output that canthen be connected to AC systems.

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STEP 4: Acquire Resources Line up resources you can call on forassistance—the earlier, the better. Thesecan include—

• Process experts. Contact your DOERegional Office (see FEMP’s Web sitefor a list of contacts). Your RegionalOffice representative can walk youthrough the process and help youwork with regulatory agencies, utili-ties, energy service providers (ESPs),energy service companies (ESCOs),national laboratories, and independ-ent consultants in your area.

• Technical experts. Programs at DOE,FEMP, and the national laboratoriesare staffed by many technical expertsin DER. Your DOE Regional Officerepresentative can help you identifythe people to contact for assistance.You might also want to contact localutilities, your state’s energy office,ESPs, ESCOs, consultants, manufactur-ers, and equipment vendors yourself.

• Financial support. In addition todirect appropriations, there are twoapproaches that Federal agencies can take to share the financial risk of a project. They are utility energyservices contracting (UESC) andFEMP’s energy savings performancecontracting (ESPC and Super ESPC)programs. These contracts allowFederal agencies to leverage private-sector financing to install energyimprovements when appropriatedfunds are not available. The utility orESCO is repaid for capital costs fromthe savings in the agency’s utility bill.Participating local utilities and ESCOscan contract for installation. Look forlocal utility rebates, tax credits, stateor Federal incentive programs, andopportunities to partner with private-sector financers, developers, andmanufacturers as well; check theFEMP Web site for more informationabout SER funding opportunities.

• FEMP DER Program. FEMP offers avariety of services to Federal agenciesthat are considering DER projects,including technical assistance,

alternative financingassistance, education,and outreach. See theFEMP Web site andcheck with your DOE Regional Officerepresentative (seeResources on p. 16)for more information.

STEP 5: Develop a Project Plan At this point, you shouldhave a specific technolo-gy approach in mind,designed to meet yourfacility’s energy needs. One of the first thingsyou will need to do isevaluate the feasibility of your DER concept.

• Feasibility. First, conduct a prelimi-nary screening of your concept toevaluate its cost-effectiveness. Thisstep takes little time, requires minimaldata, and will help you decidewhether to proceed with a moredetailed study. You can request assis-tance with this screening from yourDOE Regional Office (see Resources,p. 16) or from local vendors and con-tractors that specialize in the technol-ogy and application you selected. Ifthe preliminary screening indicatesthat the project will be cost-effective,you can move forward with a full-scale feasibility study. Again, yourDOE Regional Office or local vendorsand contractors can assist you. Youwill need to reevaluate the cost-effectiveness of the project every timeyou add new costs and benefits. If the results of the feasibility study arepositive, you can then prepare a moredetailed project design. This designdetermines the specifications stated in your request for proposals (RFP).

If the results of your feasibility study are positive, you can start developing aplan to have your DER system financed,built, and installed. You will also need to complete the tasks below that apply toyour project. (For example, air emissions

permits are not required for PV systems.)These tasks should be done concurrently,since they are largely independent ofeach other. Note, however, that permitsand utility connections can be costly; thiscould change the economic viability of a project that looked promising in thefeasibility study.

• Financing. Explore financing options,using the resources described inStep 4, where possible. Contact yourState Energy Office, DOE RegionalOffice representative, or local utilityto see if any incentive programs areavailable to help with the cost of yourDER system.

• Air Permits. Apply for air permitsfrom the local air resources controlboard, as needed. Depending on thesize, type, and potential impacts ofyour project, this can take up to sixmonths for technologies having emis-sions. Fees will be assessed to evalu-ate the project, and will probably beproportional to the expected totalyearly emissions. See Step 6 for addi-tional information on air permits.

• Utility Connections and Rates. Apply for interconnections with localutilities. This includes electric inter-connections for all DER projects connected to the utility, and gas line interconnections for projects

DOE FEMP can help your agency obtain innovative financing forDER projects.

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requiring gas at higher volumes andpressures than the gas distributionsystem can provide. Typically, youwill file an application with the utili-ty, providing basic information aboutthe proposed project and enclosing anominal payment for processing and review. You will be informedafter a specified period (typically, two to three weeks) whether a moreinvolved study is required, what itwill include, what it will cost, andapproximately how long it will take(typically, about six weeks). Thisstudy will then describe the utilitysystem upgrades (if any) that are nec-essary, what they will cost, and whenthey can be scheduled. It is then up toyou to evaluate the cost in relation toyour project’s total cost and projectedsavings, and decide if your project isstill cost-effective. See Step 6 for moreinformation.

Utility rate impacts should also beinvestigated carefully. A new DERsystem can change your facility’senergy demand and thus your ratestructure. Large, gas-fired DER sys-tems have high, consistent fueldemands, though you might be ableto negotiate a lower fuel rate.Interruptible electric rates may pro-vide cost savings if the DER systemprovides backup power. It is a goodidea to look into anything that cansave money and improve the eco-nomics of your DER system.

STEP 6: Address PotentialBarriers As your project nears completion, youwill need to work with various entitiesto obtain permits, connect to the utilitysystem, and perform other activitiesexternal to your facility. Some of theseactivities will require more time, effort,and money than you originally estimat-ed and may pose certain barriers youwill have to overcome. This section will help you identify potential projectbarriers; estimate their impacts on yourproject in terms of additional time,money, and expertise required; and for-

mulate plans and strategiesto overcome or avoid them.

Overcoming technicalbarriersThese barriers relate prima-rily to your local utility'selectrical interconnectionrequirements, which aremeant to ensure that yourDER will not negativelyimpact the reliability, safety,and power quality of theelectric grid system. Othertechnical barriers caninclude fuel availability orstorage; space limitations;power quality impacts; fire,safety, and zoning require-ments; and operations andmaintenance issues.

You can begin by finding a contact per-son at the utility and asking for intercon-nection guidelines. Although the utilitymight not have established formalguidelines or rules, someone thereshould be responsible for handlinginterconnection requests.

Some utilities have expedited or simpli-fied rules for certain types of DER. Forexample, renewable energy systems pro-ducing less than 10 kW may requirenothing more than an inspection by theutility. Larger DER installations mayrequire an engineering review, or even afull-fledged study. A study can take autility from two to six weeks to perform,and you will probably be required topay the utility's costs to conduct it. Theresult may be that protective equipmentor other hardware must be installed, andyou will be required to pay for that as well.

How can you tell if the utility's demandsare appropriate for your specific installation? And how do you make surethat the process is handled with a mini-mum of delays? Here are some tips:

• Find someone to be your point of con-tact at the utility and maintain thisthroughout the process. A recentstudy, Making Connections: CaseStudies of Interconnection Barriers and their Impact on Distributed Power

Projects (see Resources on p. 16),found that this was a consistent factor among projects that reportedtimely progress in obtaining interconnections.

• Ask the utility contact for properapplication forms, and make sure youunderstand the technical data theyare requesting. You or the contractorwill have to provide these data whenapplying, and you may need to con-tact equipment vendors or otherresources to obtain the data.

• Ask the utility to specify how long itwill take to process the application,and what fees must be submittedwith it.

• Utility commissions in some stateshave established regulations specify-ing the interconnection process. Finda contact person at your state's utilitycommission and ask for any guide-lines or rules that apply. Also, askwhom to contact for dispute resolu-tion, if that becomes necessary.

• Requirements for smaller DER sys-tems should be easier, especiallythose for renewable energy systems.For installations under 10 kW,requirements are often minimal tonone, particularly for renewable energy systems. For systems up to100 kW, a study is likely to be

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PV systems generate no emissions and are exempt from airpermitting requirements.

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required, but it should not take morethan a few hours for the utility engi-neer to determine impacts, and inter-connection requirements should notbe great. Above 100 kW, the impactson the utility system can be signifi-cant, so more study is likely to beneeded, and interconnection costs are likely to be higher.

• If the DER will be used for on-sitepower requirements only, and nopower will be exported or sold backto the utility, the interconnectionrequirements may be different fromthose for an exporting condition. Forsafety, utilities will require that theDER have protection equipment thatwill disconnect it if the utility systemshuts down.

• If the utility has an interconnectionhandbook, as many do, it will specifythe process and requirements, bothfor the utility and for the DER appli-cant. It should also specify time limitsfor various steps in the process, andwhat costs must be borne by theapplicant.

• Some utilities have expedited rulesfor "certified" DER equipment, i.e.,systems that have been tested andapproved for use on the utility's distribution system.

• The Institute of Electrical andElectronics Engineers (IEEE) is developing a standard, labeled P1547,for interconnection of DER facilities;although it had not yet beenapproved by the date of this publica-tion, many states are adopting similarrules. If your facility meets this pro-posed standard, this should expeditethe process.

• If possible, find out what other facili-ties in your utility’s service area havedone or are considering in terms ofDER projects. Other facility managersmay be able to offer you valuableadvice based on their own experiences.

If your DER project involves the use ofnatural gas or propane, don’t forget tocontact your local gas utility if it is notthe same as your electric utility. Your gasutility may have additional or different

requirements and procedures for imple-menting DER projects.

Overcoming regulatory barriersMoving to the operational stage in aDER project means obtaining numerouspermits and approvals. These can beeconomic as well as regulatory barriers,because time, effort, and money go intoovercoming them. Since many permitsrequire fixed fees regardless of the sizeof the DER project, the impacts on small-er projects can be greater than those forlarge projects. The Making Connectionsstudy documented numerous cases inwhich the economics of small projectswere seriously impacted by the costs ofmeeting regulatory permitting, wheresuch costs were a smaller percentage oflarger projects.

Other barriers arise because of utilityregulations. Standby charges areassessed because the utility is obligatedto serve your load if the DER is notavailable, and the utility must maintainadequate distribution facilities. Exit feesrepay the utility for distribution facilitiesalready built that are "stranded" becauseyour DER reduces the utility's return oninvestment. Similarly, regional transmis-sion charges may be assessed for strand-ed transmission assets. Ask the utilitywhat charges apply in your case.

Environmental permitting (primarily,obtaining an emissions permit) is probably the single most arduous andcostly task in getting a DER online.Contact your state or local air qualitymanagement agency in charge of enforcing air regulations. Ask them the following:

• What are the air emission regulationsin my area?

• How do I apply for an emissions permit?

• What data do I need to supply?

• What are the fees for the permit?Typically, fees are proportional to the expected amount of annual pollutants. Renewable systems andfuel cells should require minimal permitting, because they have virtually no emissions.

For most states, air permit requirementsand the required forms are available onthe Internet.

Note that even if the DER displaces anolder, less efficient or more-pollutingsource, it may be treated as a “newsource” and be subject to much morestringent emissions requirements. Some states make an allowance for theemissions reduced by using CHP (seepage 9), which could make permittingrequirements less stringent. However,most states do not make such anallowance, so be sure to ask the air regu-latory agency whether CHP allowancesare given in your state.

Land use or conditional use permitsmay be required by the local city orcounty government, and will depend onzoning regulations governing the site.Find a contact at the local planningdepartment and ask your contact whatpermits are required, what the requisitefees are, and what the application processand schedule are. A public hearing mightbe required, which is also an excellentopportunity to make a positive presenta-tion on your project to win local support.

It is often possible to require a contractorto obtain all the studies, permits, inter-connection agreements, and other require-ments as part of a turn-key design/build/operate contract. You can exploreoptions for such a contract when consid-ering financing alternatives. Ask poten-tial DER developers what options areavailable and appropriate for your site.

STEP 7: Install and OperateYour DER!Now you are ready to build and operateyour new DER system. Congratulations!You are adding an important new ener-gy source to your facility that will bringmany benefits to your operations andimprove your bottom line.

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14

Did you install all cost-effectiveconservation measures?

Analyze your facility's energyneeds and infrastructure.

Select candidateDER technologies.

Screen technologies forshowstoppers.

Are technologies stillfeasible?

Perform economicanalysis of

technologies.Are they cost-effective?

Acquire project resourcesand technical assistance.

Install and operateyour DER.

Select financingmethod.

Apply for air,land use, etc.,

permits.

Apply for and acquireelectric and gas

interconnections.

Solicit andevaluate

contractor bids.

Energyaudit

Implement energyconservation measures.

No

Yes

STOPNo

No

Yes

Yes

DER Process Flowchart

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15

Glossary of TermsAC — alternating current

Btu — British thermal unit(s)

CHP — combined heat & power

CO — carbon monoxide

CO2 — carbon dioxide

DC — direct current

DER — distributed energy resources

ESCO — energy service company

ESP — electric service provider

ESPC — Energy Savings Performance Contract

IEEE —Institute of Electrical and Electronics Engineers

interconnection — the physical connection of distributed energy resources to the utility system in accordance with prevailing regulations and standards, so that parallel operation can occur

inverter — a machine, device, or system that changes DC power to AC power (see IEEE Standard 100)

kV — kilovolt(s), an amount of voltage equal to one thousand volts

kW — kilowatt(s), an amount of power equal to one thousand watts

kWh — kilowatt-hour(s)

MW — megawatt(s), an amount of power equal to one million watts

NOX — oxides of nitrogen

O&M — operation and maintenance

PCU — power-conditioning unit; an inverter

PM — particulate matter

PQ — power quality

PV — photovoltaic(s)

SOX — oxides of sulfur

UESC — Utility Energy Services Contract

VOC — volatile organic compounds

volt — unit of electric potential

watt — unit of power

Produced for the U.S. Department of Energy by the NationalRenewable EnergyLaboratory, a DOE nationallaboratory

DOE/GO-102002-1520May 2002

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Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste

ResourcesFederalDepartment of Energy — Federal EnergyManagement Program (FEMP)www.eren.doe.gov/femp

Department of Energy — Distributed EnergyResources Programwww.eren.doe.gov/der

Department of Energy — Regional Office FEMPRepresentativeswww.eren.doe.gov/femp/aboutfemp/fempcontacts.html.#regional

Department of Energy — Office of PowerTechnologieswww.eren.doe.gov/power

FEMP Design Assistance Programwww.eren.doe.gov/femp/techassist/designassist.html

FEMP New Technology Demonstration Program(NTDP)www.eren.doe.gov/femp/prodtech/newtechdemo.html

FEMP Federal Technology Alertswww.eren.doe.gov/femp/prodtech/fed_techalert.html

FEMP Renewable Energy Resourceswww.eren.doe.gov/femp/techassist/renewenergy.html

FEMP SAVEnergy Programwww.eren.doe.gov/femp/techassist/savenergyprog.html

FEMP Software and Analytical Toolswww.eren.doe.gov/femp/techassist/softwaretools/softwaretools.html

DOE Software and Analytical Toolswww.eren.doe.gov/buildings/tools_directory/

Federal Incentives for Commercial SolarApplicationswww.mdv-seia.org/federal_incentives.htm

Green Power Network — State Net MeteringProgramswww.eren.doe.gov/greenpower/netmetering/index.shtml

Making Connections: Case Studies ofInterconnection Barriers and their Impact onDistributed Power Projectswww.nrel.gov/docs/fy00osti/28053.pdf

Building Life-Cycle Cost (BLCC) Software Tool forDownloadwww.eren.doe.gov/femp/techassist/softwaretools/softwaretools.html

IndustryEdison Electric Institutewww.eei.org

Energy-efficient Product Informationwww.energystar.gov

Engine and Turbine Manufacturers Directorywww.dieselpub.com/catalog/

United States Fuel Cell Councilwww.usfcc.com

Online Fuel Cell Information Centerwww.fuelcells.org

Fuel Cell Developershttp://216.51.18.233/fcdevel.html

Solar Energy Industries Associationwww.seia.org

Database of State Incentives for Renewable Energywww.dsireusa.org

American Wind Energy Associationwww.awea.org

Electricity Storage Associationwww.energystorage.org/

Distributed Power Coalition of Americawww.distributedpower.com

National Association of Regulatory UtilityCommissionerswww.naruc.org

Institute of Electrical and Electronics Engineerswww.ieee.org

Distributed Utility Associates, Livermore, California,contributed to the preparation of this guide.

For More Information

FEMP Help Desk(800) 363-3732International callers pleaseuse (703) 287-8391Web site: www.eren.doe.gov/femp

General Contact

Shawn HerreraProgram ManagerFederal EnergyManagement ProgramU.S. Department of Energy 1000 Independence Ave., SWWashington, D.C. 20585Phone: (202) 586-1521Fax: (202) 586-3000shawn.herrera@ee.doe.gov

Laboratory Contacts

Distributed EnergyResources:Trina BrownNational RenewableEnergy Laboratory1617 Cole Blvd.Golden, CO 80401Phone: (303) 384-7518Fax: (303) 384-7411trina_brown@nrel.gov

Combined Heat andPower:Patrick HughesOak Ridge NationalLaboratoryP.O. Box 2008, Bldg. 3147Oak Ridge, TN 37831-6070Phone: (865) 574-9337Fax: (865) 574-9329hughespj1@ornl.gov