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Santa Clara University leading the way in green technology. 2011 - 60 rooftop solar panels installed on the roof of the student center. The panels heat water and run the AC.
Santa Clara’s solar panels are expected to reduce natural gas use at the student center by 70%. This could eliminate as much as 34 tons of CO2.
Santa Clara leased the system for 10 years, and pay a fixed price for the energy that it creates. SCU also received $86,000 in rebates from California.
Santa Clara is not alone. Heating and cooling account for 56% of a home’s energy use.
Green heating and cooling systems: passive and active. Passive
Capitalizes on nature. Light colored roofs (to reflect heat) Double-paned windows (to insulate heat/cold)
Active Mechanical Solar panels Geothermal power
Gaining popularity Americans saved $19 billion in 2008 thanks to green energy systems. But they’re not cheap - $30 -$80 per square foot. Government incentives to help offset costs.
Geothermal The earth is HOT! Heat is energy. Use an underground well to capture the heat. A liquid (water or refrigerant) captures the
energy to either heat or cool a house.
Solar (passive) Uses the existing building (walls, windows, roof, etc) to store and release
energy. “Direct gain” systems - such as windows which trap heat inside.
Solar (active) Cells/panels contain photovoltaic materials, which directly convert sunlight to electricity. Not efficient - only convert 10% of the sun’s total power Expensive - $27,000 to $36,000 to install. Could take 12 to 15 months to recoup the
investment.
Biomass Energy derived from living things. Firewood More sustainable and cheaper than oil,
natural gas or propane. Hydronic Heating
Radiators, boilers, etc. In a hydronic system, heat is transferred in
three ways: conduction, convection and radiation.
Absorption Not driven by electricity Driven by a natural gas burner Use a water-ammonia solution, not a
refrigerant Absorbs heat in winter, repels heat in
summer
Biodiesel Not just for auto engines any more The so-called BioHeat blends contain 5 percent, 10 percent or 20 percent biofuel mixed with heating oil. Can be used in an oil furnace BioHeat releases fewer pollutants
Ice-powered air conditioners Ice Energy Makes ice at night (while it’s cooler), to cool existing AC units’ refrigerants during the day.
Here's how it works: At night, the unit freezes 450 gallons (1,703.81 liters) of water by
circulating refrigerant through a system of copper coils. The water that surrounds the coils
turns to ice, which is then stored. As temperatures rise the next day, the existing AC unit
stands down, and the ice, rather than the AC unit’s compressor, cools the hot refrigerant,
which keeps the building temperature nice and comfortable and cuts overall energy
consumption by about 30 percent
Green coal Wait, what? “Gasification” - use the carbon in the
coal to bond to the oxygen in water, which produces hydrogen, a clean-burning fuel. Waste is solid, and can be buried.
Wind Turbines don’t need to be huge to be
effective. Students at Oregon State created pint-
size turbine attached to a water heater. The only requirement is enough wind,
to spin magnets, which heats a copper plate, which heats the water.
So to sum up Green Energy is more accessible than
one might think.
