SOLAR 101 Solar energy can be used to supply electricity to a house, run a car, and heat everything from the water heater to the hot tub. There are three main types of solar energy: photovoltaic, solar thermal, and passive solar. Photovoltaic technology is perhaps the most familiar. Electron-packed panels are installed on or near a home or business. Sunlight releases electrons, and the flow of electrons creates electricity, said Doug Shoemaker of the Minnesota Renewable Energy Society. Advances in nanotechnology now make it possible to create paper-thin panels. Researchers have also applied “solar paints” to a test-lab home, transforming it into a huge collector. “In one hour, the Department of Energy reports that there’s enough (sunlight) striking the earth to take care of our energy needs for one year,” Shoemaker said. “It’s extremely important that we figure out ways to use that potential energy source.” Solar thermal technology can be used to heat water or air. In water-heating applications, the sun heats liquid in a panel that leads to a collector. The hot fluid is transported to water heaters, swimming pools, and heating systems. In air-heating applications, the air from a building is forced through a collector, warming it and returning it to the building. Passive solar technology captures the
natural heat from the sun using glass window panes on the south side of a building.
STRONG SUITS Solar-powered systems Doug Shoemaker, Minnesota Renewable Energy Society can work efficiently in most settings, either as primary or supplemenCHALLENGES tary sources of energy and heat. A system Like wind, solar power can be inconsistent. can be mounted on the ground, a building, Captured energy varies daily based on the or pole to easily provide an unobstructed amount and strength of sunlight. On cloudy view of the sun. Consumers who capture days, a backup system may be necessary. excess solar energy may be eligible for finanSolar energy systems can also be expencial incentives if the energy can be returned sive. According to Shoemaker, the average to help power the state’s energy grid. three-to-four KW photovoltaic system in According to Jason Edens, founding Minnesota costs $30,000 to $40,000 and director of the Rural Renewable Energy supplies about 30 to 40 percent of home Alliance (RREAL) in Backus, solar-based energy needs. Edens creates systems for conservation could make a huge impact on smaller homes and low-income residents for future energy needs. Funded in part by the $6,000. Costs vary depending on home Initiative Foundation, RREAL provides passize, energy usage, and efficiency. sive solar systems that help families in poverty use 25 percent less energy to heat their homes. Edens plans to replicate the React at IQMAG.ORG program across the Midwest. Fall 2008
21