Alternative Solar Energy Tips & Advice
Alternative solar energy is a great way to save money all around your home. The first thing you think about when your hear ‘solar energy’, is, of course, hot water. But there are so many other functions around the house that can be handled by solar energy. For example, you can build a solar cooker that simply focuses the sun’s rays to cook your food. With simple low-energy solar cells, you can pump water to a fountain or keep a water flow in a fish pond. Landscape lighting can be powered by these same type of solar cells, and incorporating solar design efficiencies into the design of your pool or spa offers enormous payback. But let’s focus on the big four: passive home design that incorporates solar energy use, solar water heaters, low-cost projects using solar cells, and a DIY project that uses solar cells as your alternative to utility power.
Passive Solar Home Design
The use of passive solar design in a house is the most efficient way to implement solar power. Some techniques are:
- placing insulated large windows on walls facing south.
Tip: Keep all south-facing window glass clean.
- locating a thermal mass (a concrete slab floor or wall) close to a window that will be sunlit.
Tip: Do not block sunlight falling on floors or walls.
- using insulating curtains on these large windows at night to heat loss.
Solar Water Heaters
You can satisfy anywhere from half to almost all of your need for hot water in your home with a solar water heater. The choices available to you depend a great deal on your climate and your water use.
All solar water heaters incorporate two basic features, a heat collector and a storage tank. They can be classified as either active or passive. A passive (or direct) system has no pumps, and is longer lasting, easier to maintain, and less expensive than an active system. An active (or indirect) system has controls and pumps to move heat transfer fluids from the collector section to the storage section where the home’s water is heated. Both types either require the use of conventional water heaters as a backup, or act as a pre-heater for a conventional unit.
A passive system, because it circulates water outside, is not an appropriate choice for locales with freezing temperatures. An active system, because the heat transfer fluids act as a kind of anti-freeze, does not have this problem.
Solar Cells for Small Projects
Solar energy directly powers photovoltaic cells, silicon semi-conductors that actually turn sunlight into electrical current. A DIY person would find a small solar cell project interesting, perhaps as a precursor to the large-scale project described next. You do have to have some electrical knowledge, and some soldering skills, for projects incorporating solar cells. You can find plans online for all types of projects: fountains, attic vent fans, motion detectors, battery chargers, timed sprinklers, solar ovens, water purification systems, and many more.
Solar Cells as an Alternative to Power Utilities
Once you’ve got a feel for how to hook solar cells together and push the resulting electricity where you want it, you can try a large-scale solar cell electric generator. Plans are available online and in books. You can buy all the parts for several hundred dollars — the biggest expense will be the solar cells themselves. Try building the portable version before you try the power-grid tie-in (for which you will have to bring in a licensed electrical contractor for the final hookup). Besides the wood and plexiglass to be used to house the solar cell collection (and the wiring), you’ll need to buy a charge controller, an inverter (to switch the phase), and a deep-cycle battery — all available at your local hardware store. The result will be a system that will power a laptop and several other household devices, or a refrigerator by itself.