Wednesday, February 14, 2007 - 9:35am
Madison - Mayor Dave Cieslewicz said today that the City of Madison is savings taxpayers money and protecting the environment thanks to a new solar-powered water heating system at Fire Station #8. The solar thermal system provides hot water for the ten firefighters who work out of the station on Madison's east side.
"This is just the latest way that Madison city government is doing its part to reduce our contribution to global warming," said Mayor Cieslewicz. "In combination with similar initiatives such as our purchase of hybrid diesel-electric Metro buses, we are making a sustained commitment to protecting our air quality and reducing our dependence on non-renewable energy sources."
The system generates 10.49 MwH (or 358 therms) of heat per year, which represents 3.28 tons of CO2 emissions. Solar energy heats the water which is then pumped to the storage tanks (solar loop). There the hot solar-loop water goes through a heat exchanger and heats the water in the tank. This preheated water will flow into the gas water heater.
What about the energy to run the pumps in the solar loop? This issue is addressed with pumps that run on Photovoltaic (PV) panels which are visible on top of the thermal collectors. These panels convert sunlight directly into electricity which runs the electric motors in the solar-loop pumps. That way the solar hot water system runs even during a blackout.
During summer time the solar-heated water may reach 160° F, meaning the gas water heater does not need to run at all. During winter the solar water may reach 100° F, and the gas water heater only has to provide energy to heat the water up to 120°F. In addition to energy savings, the life of the gas water heater will be greatly extended.
"The City conducted solar site and energy assessments on 30 of its buildings, strategically targeting those with the biggest environmental bang for the buck," reports Sherrie Gruder, UW-Extension and chair of the City's Sustainable Design & Energy Committee. "This solar thermal installation is the first of many budgeted for our city fire stations as Madison acts on its Green Capital City Blueprint to become a leader in sustainable energy."
"We strive to be innovative in our use of technology for the safety of our firefighters and our community," Fire Chief Debra Amesqua said. "It's important to us that we extend that innovation to protect the environment as well. We see this as a valuable opportunity to do that."
The $15,997 cost for the system was partially offset by a $3,376 grant from Focus on Energy. With projected energy savings, the system is expected to pay for itself in just over 10 years. The system was installed at a discount by "Seventh Generation" and its energy output is being monitored with a BTU-meter provided by MGE.
- George Twigg608-266-4611