Renewable Energy

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Transcript of Renewable Energy

Professor Hector R RodriguezSchool of BusinessMount Ida College

Course Map – Topics Covered in Course• Society

– The Corporation and Its Stakeholders– People for the Ethical Treatment of Animals– Corporate Citizenship– The Social Responsibility of Business– The Shareholder Primacy Norm– CSR, Citizenship and Sustainability

Reporting– Responsible Investing– The Community and the Corporation– Taxation and Corporate Citizenship– Corporate Philanthropy Programs– Employees and the Corporation– Managing a Diverse Workforce

• Environment– A Balanced Look at Climate Change– Non-anthropogenic Causes of Climate

Change– Sulfates, Urban Warming and Permafrost– Conventional Energy– The Kyoto Protocol– Green Building– Green Information Technology– Transportation, Electric Vehicles and the

Environment– Geo-Engineering– Carbon Capture and Storage– Renewable Energy– Solid, Toxic and Hazardous Waste– Forests, Paper and Carbon Sinks– Life Cycle Analysis– Water Use and Management– Water Pollution

• The term renewable energy generally refers to electricity supplied from renewable energy sources. These energy sources are considered renewable sources because they are continuously replenished on the Earth

What is Renewable Energy?

WIND HYDRO SOLAR

BIOMASS GEOTHERMAL WAVE POWER

Wind Power

• Wind power is one of the fastest-growing sources of energy around the world. It provides a clean and local source of electricity, as opposed to imported fossil fuels. – In the United States, the

Department of Energy has estimated that wind power could account for 20 percent of the nation’s electricity supply by 2030.

What is it?

How Does it Work?

Source: http://www.windenergysystems.info/wp-content/uploads/2009/11/how_wind_turbine_works.jpg

Where is it? (Watch Video)

Wind Capacity Increasing

Source: American Wind Energy Association U.S. Wind Industry Annual Market Report – Year Ending 2009

2009 U.S. Wind Power Project Locations

Source: American Wind Energy Association U.S. Wind Industry Annual Market Report – Year Ending 2009

Wind Capacity Increasing

Source: American Wind Energy Association U.S. Wind Industry Annual Market Report – Year Ending 2009

• At the moment, though, wind accounts for just 1 percent of United States electricity use. It has two main problems. 1. The wind does not blow all the time, so there must be backup

power plants ready to turn on if the wind slows. 2. The wind sometimes blows the hardest in remote plains, far from

cities that need the energy and building transmission lines is expensive and difficult.

• Other Concerns– Locating the wind turbines in or near the flyways of migrating birds

may result in them flying into the rotating blades. – Noise caused by rotating blades (inaudible beyond 1.5 miles)

Wind Power Challenges

Source: Kate Galbraith (Feb. 19, 2009)

• The idea of building wind farms offshore is gaining momentum. Putting turbines in the water is expensive, but the advantage is that the wind blows much harder off the coasts. Offshore breezes also tend to be strong in the afternoon, matching the time when people are using the most electricity.

Wind Power

• The nation’s first planned offshore wind farm; it would cover 24 square miles in the sound, an area roughly the size of Manhattan. Opposition includes:– Two Massachusetts Indian tribes, who said the 130 proposed wind

turbines would thwart their spiritual ritual of greeting the sunrise, which requires unobstructed views across the sound, and disturb ancestral burial grounds

In Our Backyard: Cape Wind Farm

– Senator Edward M. Kennedy, whose family compound in Hyannis Port looks out on the proposed wind farm site, was the project’s most powerful opponent until his death last August.

What Lesson can be Learned Here?

• Kern County, California, went Republican by 18 points in the last election. Now it's captivated by wind and solar power. Here's why– Wind farms are placed on unusable

private land– Developer covers initial costs– Land increases in value– Community tax receipts increase– Owners receive annuities– It protects public spaces

• Which makes conservationists happy as well

“Renewable Energy Catches on in Red America”

What Lesson can be Learned Here?Source: OnEarth, February 28, 2010

Hot updrafts rising from the sun-baked Mojave Desert create low pressure at

the surface, which sucks in cold, dense air from the Pacific Ocean to fill the void.

This thermal effect is one of the most ferocious wind machines on earth.

• The United States Department of Energy describes the derivation of power from water this way: – "Water constantly moves through a vast global cycle, evaporating

from lakes and oceans, forming clouds, precipitating as rain or snow, then flowing back down to the ocean. The energy of this water cycle, which is driven by the sun, can be tapped to produce electricity or for mechanical tasks like grinding grain."

• The most common method for achieving hydropower is through building an impoundment facility, or dam, where water is backed up into a reservoir and then released through turbines as needed to meet energy demands. – Diversion and micro hydropower are options as well.

What is it?

How Does it Work?

• Head – Water must fall from a higher

elevation to a lower one to release its stored energy.

– The difference between these elevations is called head

• Dams: three categories– high-head (800 or more feet)– medium-head (100 to 800 feet)– low-head (less than 100 feet)

• Power is proportional to the product of head x flow

http://www.wapa.gov/crsp/info/harhydro.htm

Some Additional Terminology

Francis Turbine – Grand Coulee

Where is it?

• The technology remains highly controversial, however, given the broad impact on local land and water resources that often attend large dam projects.

Challenges

Source: R.M. Schneiderman, February 24, 2009

The city of Kaixian was relocated to make way for the reservoir behind the Three Gorges Dam in China. Images courtesy of Ohio State University.

Two space views of the Yangtze River, before the Three Gorges Dam was built (photo below) and after the dam was completed.Images courtesy NASA Earth Observatory

– Can sometimes fail, causing catastrophe

• Johnstown flood (city just east of Pittsburgh, PA) killed 2,200 people when dam broke.

• Dam failure in China killed 230,000.

Dams and Diversions• On the downside, dams

– Drown free flowing rivers– Submerge farmlands and towns– Block fish migration e.g. salmon– Change aquatic habitats for native species

• The Environmental Protection Agency also notes that "if a large amount of vegetation is growing along the riverbed when a dam is built, it can decay in the lake that is created, causing the buildup and release of methane, a potent greenhouse gas."

Hydroelectric Power

Source: R.M. Schneiderman, February 24, 2009

Hydroelectric Power

Hydroelectric Power

Tallest Dam in the world: Rogun in Tajikistan at over 1,000 feet

http://www1.eere.energy.gov/windandhydro/hydro_plant_types.html

Sample Diversion Hydropower (Tazimina, Alaska)

• Smaller dams and newer diversionary technologies may provide alternative means for harnessing water power while reducing the overall environmental impact.

• The Department of Energy is currently exploring “low-head, low-power" hydropower technologies, which would produce energy on a smaller scale and with a smaller overall footprint.

Sample Micro-Hydroelectric Power

Energy (Pumped) Storage

• Energy (Pumped) Storage– Two way flow– Pumped up to a storage reservoir and returned to a lower

elevation for power generation• A mechanism for energy storage, not net energy production

Energy Storage in Our Backyard – Northfield Mountain

• In 1972 its 1,080-megawatt hydroelectric plant became operational as the largest such facility in the world.

• The plant was built entirely underground• Purpose – energy storage

– Water pumped uphill at night• Low usage – excess base load

capacity

– Water flows downhill during day/peak periods

– Helps Xcel to meet surge demand

• E.g., air conditioning demand on hot summer days

Emerging – Combined Hydro and Wind Power (Video)

Solar Power

• Solar power is electricity generated from the levels of natural energy contained within the suns rays (solar radiation).

What is it?

Above a scorched plain outside Seville, Spain, reflected sunlight reflects again off low clouds. Ordinarily the mirrors at Abengoa Solar's PS10 station beam searing, concentrated light to the top of the "power tower," heating a boiler that makes steam to drive a turbine. On overcast days, operators aim the mirrors skyward; sudden sun through clouds could heat the tower so quickly it could be destroyed.

• There are several ways to use the sun’s power to generate electricity. – Concentrating solar power

systems concentrate sunlight to make steam, which is converted into electricity through a turbine.

– Photovoltaics - Some materials exhibit a property known as the photoelectric effect, where photons of light knock electrons into a higher state of energy which create electricity.

How Does it Work?

Photovoltaic system 'tree' in Styria, Austria

Concentrating Solar

At Nevada Solar One near Las Vegas, oil piped down long rows of reflectors soaks up focused sunlight, becoming hot enough to make steam and run a 64-megawatt power plant. Utilities often favor such systems, also called solar thermal, over costlier PV.

Where is it?

• The main drawback to solar power is that it is expensive to produce: – Generating power from photovoltaic panels costs more than four

times as much as coal, and more than twice what wind power costs.

• Most solar cells are made with silicon, which is expensive.

– In the United States, the federal government and states have offered a variety of incentives to encourage homeowners and businesses to put panels on their roofs, and for utilities to buy power from large displays.

Challenges

Source: Kate Galbraith (Feb. 19, 2009)

Biofuels

• Biofuel - they take carbon out of the atmosphere while it is growing, and returns it as it is burned.

What is it and how does it work?

– If it is managed on a sustainable basis, biomass is harvested as part of a constantly replenished crop.

How Does it Work?

Where is it?

• Food prices are trending up due to the transfer of corn from food crops to ethanol production.

• Critics have also questioned the carbon mitigation claims surrounding biofuels.

• Environmental degradation of lakes, streams, and coastal waters due to increased nitrogen flows.

“The cost disadvantage of producing biofuels is significantly higher than

the benefits achieved from their use. This scenario is unlikely to change until 2015, even with the use of second generation biofuels.”

Kaushik Madhavan, research manager, Frost & Sullivan

Challenges

• Geothermal energy is clean, renewable energy from heat simmering within the earth's bedrock. – The earth's heat is always there waiting to be tapped, unlike wind

and solar power, which are intermittent and thus more fickle. – According to a 2007 geothermal report financed by the Energy

Department, advanced geothermal power could in theory produce as much as 60,000 times the nation's annual energy usage.

• Its main benefits are:– Providing reliable electricity at a stable price– Generates electricity in a manner that produces minimal

environmental impacts and emissions;– Generates economic development opportunities, especially in rural

areas

What is it?

How Does it Work?

http://www.nytimes.com/interactive/2009/06/23/us/Geothermal.htmlWatch Video

Where is it?

• Because large earthquakes tend to originate at great depths, breaking rock that far down carries more serious risk. – Seismologists have long known that human activities can trigger

quakes, but they say the science is not developed enough to say for certain what will or will not set off a major temblor.

• The technique to tap geothermal energy creates earthquakes because it requires injecting water at great pressure down drilled holes to fracture the deep bedrock. – The opening of each fracture is, literally, a tiny earthquake in

which subterranean stresses rip apart a weak vein, crack or fault in the rock.

Potential for Earthquakes

• Exploration and drilling remain expensive and risky. – Drilling costs alone can account for as much as one-third to one-

half of the total cost of a project.– Detecting potentially productive geothermal reservoirs is difficult,

with only about one in every five exploratory wells drilled confirming a valuable resource.

• Using the best geothermal resources often require an expansion of the power transmission system.

• Finally, power plants and direct use systems must be located near geothermal resources because it is not economic to transport hot water or steam over long distances.

Other Challenges

Wave Power

• Ocean movements, spurred by the wind or the gravitational pull of the sun and moon, are eminently renewable, emissions-free energy sources.

• According to the United States Department of Energy, some experts suggest that as much as 0.5 to 5 times the total global annual electricity consumption of electricity could be provided by ocean waves alone.

• Unlike wind and solar power, wave energy is always available. – Even when the ocean seems calm, swells are moving water up

and down sufficiently to generate electricity.

What is it?

How Does it Work?

Wave Power Technologies

OPD Pelamis Wave Plant (‘Farm’) UK Wave Hub Wavebob

Ocean Power Delivery Pelamis Ocean Power Technology PowerBuoy TMAquaEnergy AquaBuOY

• Tidal power is a bit more limited in its potential. – Only about 40 sites on the Earth present a large enough tidal

differential to make electricity generation feasible.

Tidal Power

Source: Tom Zeller Jr., (February 23, 2009)

• At present, about 100 small companies around the world are working to develop ocean power. – However, very little

electricity is being generated from the ocean except at scattered test sites around the world.

Tidal Power – Emerging Technologies

• The device has to be able to survive storm damage and saltwater corrosion.

• The total cost of electricity is too high.• There is a potential impact on the marine environment. • Wave farms can also:

– Affect fishing grounds – Impact the pattern of beach sand nourishment, and – Represent hazards to safe navigation.

Challenges

Renewable Energy Costs

Source: http://www.beyondlogic.org/southaustraliapower/

Ranking the Renewables

Renewable Futures

Conclusion

• Benefits:– Fights global warming– Creates jobs– Supports domestic energy– Secures energy future– Varied technologies– Costs trending down– Improves health and safety– Sources are renewable

• Challenges:– Environmental damages– Harm existing industries– Land intensive– Sources tend to be remote– Sources can be cyclical– Costly– Technology not there yet– Politically challenging

What about carbon capture and storage? Let’s cover that next…