The
Solar Rating and Certification Corporation (SRCC) is a
non-profit organization whose
primary purpose is to establish National Rating Standards
for solar energy equipment. This is the only national
certification program for solar energy products.
The
SRCC provides a one-time certification, national recognition,
product credibility and standardized comparisons of
solar energy products. The SRCC state-of-the-art rating
system
is a mechanism to develop consumer confidence, and
a rational criterion for tax credit qualification and other
solar incentive programs.
The SRCC uses a computer model
to estimate the thermal performance of a solar water heating
systems under specified
conditions. These ratings are based on conditions similar
to the ones defined by the U.S. Department of Energy
for testing conventional water heaters. The annual performance
listed is an estimate of how solar water heaters could
perform over a whole year in a specific location. Keep
in mind that these ratings are only estimates based on
test conditions and that your actual performance will
vary
depending on your hot water usage and actual weather conditions.
Guidelines for the SRCC List of Certified Systems Annual
Projected Savings
1) Go the SRCC web site at www.solar-rating.org
Zone 7* = San
Diego Area
Zone 9*= South
Ventura and North Los Angeles County Area
Zone 12* = Central
Mid-State Area
Zone 16* = North
Eastern and Central Eastern California Area
2) The test results are based on a standard 50 gallon
conventional electric water heater that would consume 4,100
kilowatt hours (kWh) per year. And a standard 50 gallon
gas water heater that would consume 205 therms (including
delivered energy and losses).
3) The key test result is the last
column on the right labeled: Energy Savings. This is the
estimated annual performance of the system. This represents
the amount of energy produced by the solar system, that
did not have to be provided by
the conventional water heater.
4) Example: If a 50 gallon electric water heater consumes
4100 kWh and the Energy Savings is 3000 kWh then from these
estimates the solar system could provide 73% of your projected
annual hot water needs.
In the case of a 50 gallon gas water heater, if it consumes 205 therms and
the projected Energy Savings is 150 Therms then from these estimates the solar
system could provide 73% of your projected annual hot water needs.
5) Important
Key Point. The projected
savings is determined by how the system is sized based
on the household demand-this
is the number of people using the system. The Department
of Energy projects about 15-18 gallons of hot water per
person per day. If the system is sized based on a high
demand criteria you will have more solar hot water to offset
use of the conventional water heater. We have found that
20 gallons of hot water, per person per day is a good projection
in sizing the system. This also determines the size of
the solar storage tank. For example: based on a family
of 4 with a projected demand of 20 gallons of hot water
per person per day, the projected
size of the solar storage tank would be 80 gallons.
6) Please note these estimates are based on test conditions
and your actual performance will vary depending upon hot
water usage and available solar energy.
