In a previous “Ask the Solar Pros” interview with Mike Menkes, we learned that the Power Bill Diet can increase the return on your solar panel investment through energy-conserving strategies. But what are these strategies?
One involves using helpful gadgets, those that many of us know about, such as a programmable thermostat, and others that are less common, such as the HWR pump and the heat pump water heater. Heat pump water heaters recycle rejected heat from your air conditioning or refrigeration system and use it to heat water, thereby performing 50 percent more efficiently than a standard electric water heater. Not recommended for A/C SEER rated 12 or over.
HWR [hot water recovery] pumps attach to the water heater through the hot water pipe, constantly keeping hot water circulating to prevent the wasted energy that occurs when unused hot water sits and cools within the pipes. 2-3 gallons or more of water that normally runs down the drain during the wait is conserved. Every 1,000 homes with HWR pumps can conserve millions of gallons of water each year.
In addition to the above tools, numerous alternatives exist that most homeowners aren’t aware of. Menkes believes more homeowners should benefit from simple solutions that have somehow been swept under the rug. “I am amazed that HVAC, plumbing and/or electrical contractors have virtually kept these traditional systems a trade secret,” he says. “When I tell a homeowner/commercial building owner about these retrofits, they look amazed and always ask, ‘Is this a new technology?’”
Many Power Bill Diet recommendations don’t require the use of permits or professional installation, such as insulating hot water pipes or putting a thermal blanket on a water heater. Then there are applications such as solar control film, elastomeric roof coatings, and ceramic interior and exterior paint.
Menkes describes solar-control plastic window films as a popular retrofit measure to control solar heat-gain through windows.
“Spectrally-selective films rely on reflectivity and emissivity rather than absorption, blocking the infrared spectrum responsible for almost half the heat of sunlight while allowing much of the visible light through. Use of these films in commercial and residential applications can result in rapid payback through lowered cooling costs and decreased fading of interior drapes, carpets, furniture, and paint.”
According to Menkes, benefits to elastomeric roof coatings or ceramic paint include the following, and aside from gravel ones, every home can enjoy these benefits: