To make no excessive claims, I have to admit I burnt a fair bit of wood during the night. In the morning however, around 9 o’clock, the solar fence (nominal power 2400 W) was giving 600 W and steaming vigorously. By 10 o’clock, it had thawed and gave 940 W. Later, other panel arrays took over and wattage decreased. The energy was used to run a heat pump.
P.S. Knowing that server resources aren’t infinite, I hosted the image externally, I hope that hosting on “postimages.org” works smoothly.
Finland? How cold it is?
Estonia, just south of Finland. It was not particularly cold, only -5 C during the night in places where the sky was starry. By the time of taking the photo, there was a considerable difference between air temperature and surface temperatures - thus the steaming. :)
We got global warming here - yesterday it was +5 in Udmurtia
Wow, I would expect Udmurtia to have a continental winter at this time, but nope. :)
We have had a very mild autumn also, this is the first time ground starts to freeze a little, on the top. Tiny field roads that were unpassable by car will be passable (if one is careful) after a day or two. For me, this means: I can bring firewood with a car, not with a garden cart. :D
Snow has not bothered to appear so far. Some time every autumn, wind starts blowing from the north and the Gulf of Finland subsequently tries to evaporate and fall into Estonia. Hasn’t happened yet. Surprises us every time. :P
Is a solar fence just a fence with solar panels on it? Not some kind of barrier to keep the sun out?
It’s just a fence made of solar panels. Helps produce energy in winter, because snow cannot cover them. :)
Hi, I am very curious on your inverter / battery setting as you said the heatpump is powered by solar. Do you have a hybrid setting or do you have batteries that buffer for the heatpump. As a heatpump is quite some power and needs to have a stable power supply
Ps, living not far from you (Lithuania) and I am interested to built these fence panels for the winter as well.
I have batteries and a stand-alone inverter. Currently, there is no grid connection, the power company is still working on getting a cable here.
My batteries are not a shiny example of how to do things - poorly installed and pretty dangerous right now (batteries should not be indoors) so I’m building a battery box outside the house for them. (Of course, already now they have redundant balancers and a battery alarm.)
Currently, my battery capacity is quite low: about 10 kWh. I plan to expand that to 18 kWh.
Currently, they suffice to run the heat pump for half a day.
Often times, I operate with a partial energy balance: e.g. panels currently produce 700 W, heat pump requires 1200 W (this seems to change with outdoor temperature), I take the difference from batteries.
But in mid-winter, I use a wood-fired stove.
Also, when it’s warm enough indoors, but I feel that I need to store heat for subsequent days, I have a pool heat pump converted (more like hacked) to heat a 1 ton water tank. It circulates a solution of car windshield washing liquid (ethanol based) through a system of hoses and a long copper coil in the water tank. It draws about 600 W and make no immediate difference to room temperature.
Wauw, that’s quite a setup. Nevermind the state of things, there is always room for improvements. First is that it works. Your intake of solar is quite low compared to your battery size. Are you also aiming for more solar and bigger inverter then? Otherwise it will take days to fill 18kwh.
I am also aiming for a ton of water to be heated, both firewood and solar but have to rebuild the sauna stove for that. To have both stone and water as thermal storage. The stone I aim to also feed with cold in the summer. But I have to think more on that as condens forming is something risky.
Your intake of solar is quite low
I have other solar arrays besides the fence. Two diagonal arrays and one shed roof (which covers with snow in winter). All together they can currently give 4.5 kW. But this never happens in winter, of course.
If you cool something considerably below room temperature (specifically, the “dew point” at the air moisture level that you have), condensation will happen for sure.
I use my heat pump for cooling in summer. The indoor unit keeps dripping condensation water through a small hose into the big water tank.
