Tim
Carter
Tribune Media Services
Aug. 5, 2006 12:00 AM
Question: Soaring energy costs have me thinking about solar
energy for my new home. Have there been significant advancements in
technology with respect to solar energy and residential applications?
What kind of systems can be installed, and are they really cost-effective?
Would you consider solar energy if you were building a new home? If
so, what kind of system? Are there negative issues with respect to
solar energy?
- Pamela D.,
Montgomery, Ala.
Answer: The time for solar energy has arrived. There is not a doubt
that solar-energy systems one day will be as common as balloons at
a child's birthday party.
Solar energy makes sense for a number of reasons. Natural resources
such as oil, coal and natural gas are being used faster than geologic
processes can create them. Meanwhile, the sun's energy output is constant,
or nearly so, every day.
When the sun is shining on south-facing lots in the Northern Hemisphere,
huge amounts of energy can be captured. In fact, you might capture
excess energy that can be sent backward through the power lines to
neighboring houses. My friends in Colorado routinely do this with
their solar-energy system.
There have been significant advancements in solar-energy technology.
The biggest may be the consistently decreasing costs for photovoltaic
cells and panels and other equipment. Although solar energy is still
pricey, these lower costs translate to faster paybacks, which increase
the likelihood of a positive return on investment while you still
own the house.
There are different residential active-solar-energy systems. One
uses photovoltaic panels and cells to transform sunlight into electricity
by a natural process common to certain crystals. If extra electricity
is produced, it is stored in batteries. If the batteries get fully
charged, you can send the electricity back downstream into the electric
company power grid, if you have permission.
Another solar-energy system captures radiant heat from the sun. You
can use this heat to raise the temperature of air or water in your
home.
A solar-energy water-heating system that uses the sun's radiant heat
can be an open or closed loop. An open-loop system takes the actual
water that will be used and sends it to the solar-heating device.
This system works best in areas where freezing temperatures don't
occur. An open-loop system could freeze up in the dead of winter on
a bitter cold night.
Closed-loop systems contain a liquid in the piping system that will
not freeze. The sun heats this liquid, and the heat is transferred
to the domestic water-supply lines via a simplistic heat exchanger.
I intend to use one of these closed-loop systems in a home I am planning
to build in New Hampshire. I also intend to install a photovoltaic
system to help lower my dependence on the electrical grid.
Smart architecture also can help capture solar energy. Passive solar
energy allows you to capture the strong solar rays that can heat up
interior surfaces in your home during daylight hours. Dark natural-stone
flooring or other dense materials that can absorb solar heat work
very well. As the sun sets, these heat repositories then slowly release
the stored energy back into your home. Mother Nature gives freely
of her solar energy, so be sure not to waste that which comes your
way.
Some solar-energy systems need periodic maintenance. The solar panels
may have to be cleaned regularly to ensure peak performance. The tilt
of certain panels may have to be adjusted several times a year to
get the maximum benefit from the sun's rays. You also may have to
check batteries to ensure you have power when the sun is not shining.
http://www.azcentral.com/arizonarepublic/home/articles/0805builder0805.html