Sunday, September 2, 2007

Spring update

We're starting to get some good solar hot water now. Today we got the hot water cylinder up to 55 degrees C.

The solar PV is going very strong now as the day get longer. The charge hasn't been below 97% for weeks. The PV system is currently driving the weather station and it's data logging laptop. Over summer I might be able to switch to running the web server. I'm just a little worried my 4 Trojan T104 batteries are not enough for that load. Ideally I should add another 4 to give the PV system enough storage to last a few days of grey weather.

My purchase/wish list now is:
  1. Add 2 or 4 more Trojan T104's
  2. Add another 80 Watt PV panel (to bring the total to 4 panels)
  3. Upgrade to a 24 volt input true sine wave 1000 Watt output inverter
Step 3 means I can reconfigure the PV panel wiring to 24 volts (2 strings of 2 panels) - which will reduce the DC voltage lose over the wires.

Then I'll be ready to power the web server from solar panels all year round.

The plastic double glazing is now starting to show it's weak points:
  • if you tape the plastic out to the edge of the window frame it looks better, but in heavy winds the plastic edges start to "wheeze". They make a sound like a lamb bleating 100m away. Not entirely unpleasant - mostly odd.
  • if the window frame has any cracks in the joints - it will let in moist air. The moisture builds up and does not escape. I've got this on a sash window that I plan to restore this coming summer. I don't have this problem on the sash windows I've already restored.
The LED spotlight is working so well I jumped online to order some more. My main source was out of stock so I hunted around and found a Chinese source for 8Watt (equivalent to about 100Watts) warm white LED spotlights, for only US$30 each (plus shipping). I got 2. They are less bright than the first ones - but have a "warmer" light (ie yellower). They seem to be working fine too.

I may buy another of the previous type when they are available. Then I'll use the warm white ones out front, and the stronger cool whites on the garage overlooking the back yard and garden.

One more thing - my power company Genesis, raised our prices last month, almost doubling the line charge. Plus Genesis generates a fair bit of it's power from non-renewable sources (eg coal power stations) - so we'll switch to Meridian soon.

Cheers, Paul
paul at kennett dot co dot nz