I’ve not been in the shack all that much recently (being part of the organising team the the Irish IPv6 Summit kept me busy) so I have not been doing much checking up on the PV installation and how it is working. Today, after assisting the South Eastern Amateur Radio Group set up a station for the EI2GEO special event station, I got to sit down and do some investigations. I have a second 60 Watt solar panel that I mentioned before. We hooked it into the battery system on Jim, EI8IG’s camper van to keep the battery topped up via solar power, and ran the radio from the same battery bank. This evening I dropped out my little 850 watt generator to keep the battery topped up overnight (and to give it a good run).
Today over a 12 hour period between approximately 08:00-20:00, my rrdtool graph says the system produced an average of 148 watts. 148 x 12 gives 1776kw, or approximately 28.5 cents of electricty (including vat). If we have about 7000 more days of sunshine like today (unlikely) then the system will have “paid for itself”. While it doesn’t seem like a whole lot, it is currently averaging about 1/6 of the ESB bill (over 30 days).
That is the first part done. Next I intend to replace my power hungry dell dimension desktop (approx. 125 watts, 24/7 or approx. 48 cents per day ) with a more efficient machine (approx 20 watts or approx. 8 cents per day). To do this I have purchased an Intel Pine Trail base D510MO a 40GB SSD drive, 4GB of ram and a DC powered case (I already have a DC supply in the shack, plus I can experiment with it in the car as well).
Thus far the machine seems to be able to do most of the tasks I need it to do, time will tell though as I need to get 6 RS-232 ports operational on it to control all the items I have running.
As an aside, we recently replaced the old washing machine (at least 10 years) with a super duper A rated new one. Initial testing seems to suggest that it is no more efficient than the old one. My suspicion is that I tested the old one (which I no longer have) in late Autumn, where it would have the benefit of taking hot water from the cylinder (Central Heating). The new one doesn’t have a Hot water input, so has to heat the water itself.