Solar Power Blog

My thoughts are more on solar power lately, due to the economic climate and the recent efforts of the Halton Residents Solar Project.  I strongly support solar power, but there are two issues with solar power that have room for improvement:
  • Cost
  • Inefficiency of integration
25 years ago, solar power had a 25 year length for return on investment.  That was more for hot-water heating systems, rather than electrical generation systems which were not prevailant.  Nowadays the hot-water heating systems are closer to 10 year ROI, while the electrical generation systems are 25 year ROI.  These are certainly better, but is still expensive.  Technology will progress and costs will go down but not at a fast pace.  By addressing the inefficiency of integration, a faster ROI could possibly be achieved.
Integration inefficiency is directed at the way in which current electrical generation solar panels work.  These photovoltaic systems take energy from the solar panels and stores then in batteries.  For a household to use this energy the batteries must be run through an inverter to convert it from DC to AC.  At this point there is a loss of power anywhere between 10% to 50%.  Once the electricity is AC it flows to the household outlets and is consumed by various appliances.  Many of these appliances are electronics that require only DC electricity, so another conversion occurs in the appliances' power transformer to switch the AC back to DC.
Examples of appliances that are DC or can be converted to DC:
  • Computers
  • LCD televisions
  • HVAC systems
  • Cordless telephones
  • Gaming consoles
  • Stereos
  • Fans
After examining the house, there is a large majority of appliances that could have the transformer removed and plugged directly into a DC power bus.  The increase in saves could be significant.  The major hurdles include:
  • Retrofitting the house with a DC power bus.  (While leaving the existing AC infrastructure in place)
  • Converting appliances so they can plug into the DC power bus.
For anything with an external power transformer, the conversion is straightforward.  The transformer is removed and a regular cable is connected between DC power bus and the device.  Different cables would be required to draw different DC volts.
The more difficult appliance conversion is where the transformer is built into the device.