Post on 13-Dec-2015
DIRECT-GAIN
• Large south facing windows that let in the sunlight.
• Thermal mass is used to absorb the radiation.
• At night the absorbed heat is radiated back into the living space.
CDAE 170 Solar Building StrategiesPV system design Dec. 1, 2003
Gary FlomenhoftBSME, MAPP, CEEResearch AssociateGund Institute, SNR
Photoelectric Effect
A picture of an typical silicon PV cell
Now a short video:
http://www.eere.energy.gov/solar/multimedia.html
CZOCHRALSKI PROCESS
• This is the process of creating an ingot.
• A small single silicon rod (seed) is placed in an inert gas at high temps.
• When the seed is rotated up and out silicon adheres to it to form an ingot.
CELLS -> MODULES
• Wafers 5 inches square and .012 inches thick are sliced from the ingot.
• They are then processed into cells and soldered together to achieve the desired voltage.
• Cells arrayed in series are called modules.
MANUFACTURERS
• Sharp Electronics Corporation
• Sanyo• bp Solar• Shell• Sunwise• Uni-Solar• AstroPower
Thin Film History
• Developed in 1980
• Applied to calculators, watches and other portable low-watt appliances
• Expanded to larger appliances as efficiency rate increased
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
Cost by Brand
• Unisolar 21 watt= $153.00
• Shell 20 watt= $198.00
• Isofoton 165 watt= $650.00
-research shows that on average thin cell costs $5 per watt
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
What is an Inverter?
• An inverter is an electrical circuit capable of turning DC power into AC power, while at the same time regulating the voltage, current, and frequency of the signal
Impulse Turbines
Pelton: High head (>10ft), low flow
Turgo: Medium head (>4ft)
Crossflow: Low head, high flow
Biomass: In VermontVT Energy Consumption Sources• Nuclear 36%• System 14%• Hydro Quebec 35%• Oil 2%• Gas 1%• Other Renewable 5%• Small Hydro 7% Since 1984, Vermont has met all increase
in energy demands(a total of 125 Mw) by renewable in-state sources:
-40 Mw Small Hydro
-73 Mw McNeil/Rygate (Biomass Plants)
-6 Mw Searsburg Wind Farm
EPA Landfill Incentive Programhttp://www.epa.gov/lmop/
Kinds of Biomass-traditional
• Trees- Wood has been used as a source of energy throughout human history and today the most commonly used form or biomass. Today there are still many people in third world countries using it to provide heat and energy. There are also ‘purpose grown’ tree farms which are specifically grown to produce wood for energy in larger developed countries.
More traditional Biomass types
• Straw is used similarly too wood, it is burned and used to make heat and energy
• Animal Dung- Poop is often used as a source of heat and energy
More non-traditional Biomass
• Landfill gas- The gas emitted from landfills is very rich in methane, it is collected and used to generate power in small scale power plants.
Gasohol• Ethanol Alcohol
generated by fermenting sugar cane or corn is combined with gas and used to power cars…mmm…tasty gasohol.
BiodieselBiodiesel is made from:• vegetable oil• alcohol (20-30%)• sodium/potassium
hydroxide (2-3%)
Geothermal Heat Pumps• A geothermal heat pump system consists of
pipes buried in the shallow ground near the building, a heat exchanger, and ductwork into the building. In winter, heat from the relatively warmer ground goes through the heat exchanger into the house.
• In summer, hot air from the house is pulled through the heat exchanger into the relatively cooler ground. Heat removed during the summer can be used as no-cost energy to heat water.
Geysers
• Water at bottom of container is under great pressure and will not boil until temperature is above 100oC
• When boiling begins, a great amount of pressure is released, causing the water to boil rapidly.
• Steam-driven water, under great pressure, rushes up to the neck, and sprays steam into the air