Sunday, July 14, 2013

Record capture on sunny days, and another pump exchange

14 July 2013: The ETFE is so effective that the heat can build up almost too quickly in the big Sunbox. I've decided to leave the bottom vents open to reduce over heating risk. Although the black collectors are vertical, the liquid temperature will zoom up to over 70º if the pump is not running. If the pump is running, it is still too slow (at 2-3 litres/minute) to remove this heat and I have been tricking the GSHP into using its pump to work cold, just pumping liquid round without heating or cooling. This brings the Sunbox temperature down to about 40º on hot days.
These show the liquid temperatures in each
of the Surya panels
  I decided that it would be worth investing in a replacement faster pump, so I installed a faster speed Wilo pump this morning (only took about 20mins). This will get the energy down below faster, allowing the panels to accept more solar energy. This pump uses slightly more energy than the previous one, but during the day, it is powered by the PV roof anyway - costs nothing to run!
  Today, the total Solar capture was 59 kilowatt hours! 23kWh of this is Photovoltaic, 7kWh from the tubes (highest ever) and 29 kW from the combined Suryas (also highest ever, Surya-3 was 19 and Surya-4 was 10). The afternoon got slightly cloudy, so we havent yet had a totally maximum performance from the PV roof.
  Ground temperature is holding steady at 14.1ºC, boosted by the good weather, but also by the additional solar thermal systems added since last year.

No comments:

Post a Comment

Comments will be moderated before showing. Please make them relevant to the subject of the posting. Comments which advertise commercial products will usually be deleted.

Popular Posts