Tuesday, October 7, 2014
What will the sustainable home of the future look like? Will the solar space (the rooftops) be populated with evacuated tubes, PV, boxed and glazed, pool collectors, wind turbines, air conditioners or what exactly? Over recent years thanks to enormous efforts on the part of governments to further solar electricity (photovoltaics or PV) the cost is down and technology has advanced, so much so that we’re competing with PV for roof space almost every time we try to solar heat a pool in California! If we can cool a PV panel we can improve its performance by as much as 20%. That is solar thermal energy that we want to get rid of. The best place to dump it is into the backyard pool. Why not heat the pool as a bonus to cooling the PV? Let's talk about home and water heating. This is a storage challenge more than it is a solar collection one. Its what holds us back on most large scale solar water heating opportunities. No place for a big storage tank. We need to store that solar energy when its available so we can use it when we need it. The perfect storage tank is the backyard swimming pool. The future will be all about electricity. We have to get away from the localized burning of fossil fuels just for showers and space heat. We can do all that with electricity and we will. The future is electricity. Solar, wind, hydro, micro hydro are all carbon free and electric. But natural gas is cheap. That's the roadblock. To get more out of our electrons we employ heat pumps. These magical devices use low grade energy like that wasted from PV panels or collected by solar thermal panels, pump that energy up through a refrigeration cycle and deliver usable higher temperature heat. Heat pumps operate both ways. In other words they can cool your house and dump that excess energy. Again, where better to dump that energy than the backyard swimming pool? The future low energy home has a great big storage tank out in the yard and its part of the home. You can swim in it. If a warm pool is the sacrifice we have to make to go green then so be it.