Active Solar Heating Systems
Solar heating systems are
capable of providing most, if not
all, of your home heating and
hot water requirements with the
following systems: solar water
heating, solar space heating,
and solar pool heating.
Compared to solar photovoltaic
(PV) systems which produce
electricity, solar heating systems
are 2 to 3 times more cost
effective and offer a shorter
payback period of only 3 to 6
years on most residential hot
According to the Solar Energy Industries Administration (SEIA) solar water heating
installations grew by 10% between 2008 and 2009. Unfortunately solar pool heating
installations - tied closely to the housing industry - didn’t fare as well experiencing a
10% drop in demand during the same period.
The growth of solar installations of all types in the United States is meager compared
to other developed nations; this despite an 8 year extension of the residential solar
investment tax credit that allows a 30% credit on equipment and installation with no
This is unfortunate since most solar hot water systems range in price from only $2,000
- $8,000 and pay for themselves in just 3 - 6 years leaving you with free domestic hot
water for years to come.
Solar Water Heating
A solar water heater, if properly sized, should be able to provide 100% of your hot
water needs during the summer. But during relatively short winter days your existing
hot water heater may be needed to supplement the solar system.
Solar water heating is either active or passive. Active systems are the most common
type installation. An example is the solar hot water drain back system which
incorporates a pump and a temperature sensor to control the flow of water.
The parts of a solar heating system usually include the following:
- Insulated piping to transport the hot water
- Electronic pump and controls
- Freeze protection system in colder climates
Passive systems on the other hand have no moving parts and operate on the principal
of natural convection. One type of passive system is the thermosyphon. The
thermosyphon system is popular here and abroad because it is relatively inexpensive
and is easy to install.
Another inexpensive option for those of you with a technical background is solar hot
water heater kits available from any number of solar equipment suppliers.
Solar Heating Systems
Solar heating systems are active and usually incorporate evacuated tube collectors
rather than flat panels. Solar home heating is similar in principle to hot water heating
but the technology is applied to different use.
One way to heat your home with solar hot water is to run the hot water through a
heat exchanger installed in the plenum of your furnace. A second method is to circulate
the heated water through tubing installed either within, or under, the sub-floor, or in a
concrete slab beneath the house.
Solar Swimming Pool Heating
Solar heating for small pools is the least expensive and easiest to install method of
solar heating. The collectors are unglazed and coated instead with black polymers to
absorb heat from the sun. Most of these systems are compatible with the existing pool
filter pump and require only a few connections to get them up and running.
Although the concept of solar heating is simple its implementation can be confusing
due to a myriad of choices dictated by type of system, size of system, installation
issues and, most importantly, your budget.
Similar to any other home improvement project, the best way to avoid unnecessary
problems is to employ a certified solar installer to help you design and install your