Hi,
Thanks for that very useful information. But ...
Hmm, I wonder if you (all) appreciate how much lower is the light level in "Northern Scotland" compared with Portugal (or even CZ). Not even considering the very "Grey" days (or even weeks) that we can get in UK, the daily "insolation" (from the link in #2) for Aberdeen (not the absolute north of Scotland) in December is 0.32 kW per day, for a 1 square metre horizontal surface (I believe a typical "200 watt" rated panel). Coresponding figures for Portugal and CZ appear to be 2.0 kW and 0.7 kW respectively.
Of course there is unlilkley to be much need for power to operate "aspiration" (a fan) and Werk's panel does seem very "generous" in size. Also, the PV panel can be tilted (facing south), but the best angle can be difficult to calculate, because the slope reduces the available power from the sky (when the sun is obscured by cloud).
Whilst I do agree that LiFePO4 is an excellent technology (which I intend to use for my own much lower-power project) I do wonder if the OP should start with a much simpler (and maybe larger) SLA battery, or a much more specific power-budget calculation. A SLA could be much easier (and cheaper) to increase in capacity if required, or just to receive a "boost" from a mains charger in mid-winter, if the solar charging proves inadequate.
Cheers, Alan.
Thanks for that very useful information. But ...
(31-05-2016, 22:59)cjthomson Wrote: I have decided that a setup of a 40 Watt solar panel, charge controller and either a 12ah or 15ah battery is probably what I need to get. The prices for the parts - especially the battery are better than what I'd seen for a LiFePo4 one.
(01-06-2016, 01:20)Werk_AG Wrote: I'm using a 14Ah Pb battery and a 50W monocrystaline panel, and never had a problem. Last year we had here in Portugal a harsh winter with several consecutive days without clear sun.
Hmm, I wonder if you (all) appreciate how much lower is the light level in "Northern Scotland" compared with Portugal (or even CZ). Not even considering the very "Grey" days (or even weeks) that we can get in UK, the daily "insolation" (from the link in #2) for Aberdeen (not the absolute north of Scotland) in December is 0.32 kW per day, for a 1 square metre horizontal surface (I believe a typical "200 watt" rated panel). Coresponding figures for Portugal and CZ appear to be 2.0 kW and 0.7 kW respectively.
Of course there is unlilkley to be much need for power to operate "aspiration" (a fan) and Werk's panel does seem very "generous" in size. Also, the PV panel can be tilted (facing south), but the best angle can be difficult to calculate, because the slope reduces the available power from the sky (when the sun is obscured by cloud).
Whilst I do agree that LiFePO4 is an excellent technology (which I intend to use for my own much lower-power project) I do wonder if the OP should start with a much simpler (and maybe larger) SLA battery, or a much more specific power-budget calculation. A SLA could be much easier (and cheaper) to increase in capacity if required, or just to receive a "boost" from a mains charger in mid-winter, if the solar charging proves inadequate.
Cheers, Alan.