How did your solar fare during the January '24 freeze?

labeeman said:

My grandparents lived on the Trinity Bay.

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I was on Lake Anahuac for 20 years, which shares a levee with Trinity Bay. Who knows - I may have known them. Small world.

JBoffgrid2022 said:

What is the efficiency lost for btu output on lower temps when using a heat pump? I was always told here in Maine that although a heat pump can provide heat, it is not recommend as a primary source of heat simply because the technology lacks the ability to be efficient sources of heat due to low ambient outdoor temps. We've always used wood stoves, pellet stoves, etc because they produce so many BTU's for the money. My wood stove is rated close to 40,000 BTU's and it heats up our entire house to 80 degrees with only $20 worth of wood!

Also, if I'm not mistaken, Texas electricity costs are at $0.14/kWh. Does that mean it would cost you 180kWh x $0.14 = $25.20?
That's not terrible honestly, considering the costs of switching your heating source over as well as any offset you're getting from the solar.

F 500 V3 Oslo | Wood stoves - Traditional

F 500 V3 Oslo - Wood stoves. Tax Credit Approved

www.jotul.com

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The efficiency lost is much less on the newer equipment. The Mitsubishi's are way more efficient than the heat strips in my old units. I doubt they're as efficient as NG but I didn't want to do that whole conversion and I got a deal on the units I have. In any case, we work with what we have.

Our last bill was at $0.095 but it varies a little depending on demand. The highest I've seen was 13 cents. So yeah, it wasn't that much money to just run everything on the grid for a few days and not have to worry about it. I forgot to mention I was also running a 1300w electric heater in the shop because I have some water lines in there that have frozen in the past. So that was running 24 hours a day for a couple days and accounts for about 30kwh or so. As I recall, I was running it last year as well so the comparison from last year to this year is still valid.

My setup did pretty well. Hit 9-10F here on a couple mornings. I went on grid at 50% SOC the morning of the 14th then grid charged at 3PM to 100% to get ready for the storm and possible ERCOT shenanigans. I left us on grid at 100% SOC until 6AM the next morning since the sun was supposed to come out on the 15th and I was good to burn through a bit of battery. After that I've been back in self-consumption mode.

One cool thing is I picked up 1500W electric heaters for the three occupied bedrooms. Our 4130 sq ft house has two central heating systems (upstairs & downstairs - gas) managed by two Ecobee thermostats with individual sensors in each room. At night the setup only monitors those 3 bedrooms and I set the target for gas heat to turn on at 64F if the electric heaters couldn't hang. We went through multiple 7-8 hour overnight stretches without running any central gas heat. Ecobee shows I shaved combined daily heat run time from 18 hours in similar conditions last year to 10.5 hours. Of course, I did use more battery/power than last winter but I had plenty to spare. Worse morning (the 16th) I went from 100% the evening before down to 35% SOC @ 07:50 but was back to 100% and exporting by 13:30.

Oh...and battery temp held in my garage without any kind of heating. Lowest BMS reported temp was 9*C the morning of the 16th when it was 10*F outside. BMS requested charge limit automatically dropped from 600A to 240A (~12.3 kW) when below 18*C.

I just don't rely on electricity to keep warm. We had (are having) the coldest winter in 20 years here. This is how much it took to keep warm at -30C (-22F):

EastTexCowboy said:

I've looked at those as well, along with the wood fired boilers. I don't think that's a route we want to go but I've thought about buying one and sticking it back. The biggest complaint I've seen in reviews is the volume of wood required, but maybe they have improved the efficiency. I may take another look. Typically we don't get that much below freezing days but these last 3 years have been atypical for sure.

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Another thought is to have a vent available that you can attach a portable camping wood stove when you need it. Maybe upgrade a dryer vent (if you have one).

EastTexCowboy said:

Just curious how everyone's solar and/or batteries did/is doing during this last freeze. I'll start. Mine didn't.

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Which freeze? You mean it ended? 1°F here today.

I've been watching the solar array in a neighboring small town. It was installed to offset the cost of running the sewer plant. Blizzard was here on Saturday, I still had some production even in that. Meanwhile the arrays in that town still remain covered in snow. It doesn't melt off during the day when temps hang around 0°F and below. Meanwhile I'm getting some great PV yield.

I haven't used any grid power since January 9th when the clouds finally blew out of here with the cold temps, some days -25°F. Once the snow stayed on the ground, I've been pulling in some pretty good yields on the sunniest days. My panels tilted to 65° combined with the snow really work well. On Jan 15th, my house loads were 37Kwh and it charged the battery 25.1Kwh. That is from 8.4Kwh of array.

I've been running the heat pump and radiant heaters in the house for dump loads. I keep track of sun forecast several days ahead and plan accordingly. I can turn the heat pump on/off remotely, once battery hits over 75% and the sun is shining, the dump loads get turned on.

Cold weather like this is much better for solar production than the warmer temps we had in December with endless cloudy weeks.

I prefer choices when it comes to heat. Currently collecting everything to install a gasification boiler with 1070 gallons minimum of thermal storage and radiant floor heat. (2 year project) I'll be installing another mini split heat pump this year, plus adding some PV for the house. I'm waiting to see how much propane we use by spring in the high efficiency furnace. As I said, I like choices.

EastTexCowboy said:

We looked at adding a fireplace but it's just not practical on this house. I envy you for that! I keep kicking around adding a couple of NG wall heaters or something. It's hard to justify either considering how few days we have when it's really cold.

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Outdoor wood boiler is what I went with. Have 2 indoor stoves, but those haven't seen a single log since I got the boiler. It integrates with your regular forced air HVAC system, or with radiant heat, etc. Also heats hot water for free.

Zwy said:

Which freeze? You mean it ended? 1°F here today.

I've been watching the solar array in a neighboring small town. It was installed to offset the cost of running the sewer plant. Blizzard was here on Saturday, I still had some production even in that. Meanwhile the arrays in that town still remain covered in snow. It doesn't melt off during the day when temps hang around 0°F and below. Meanwhile I'm getting some great PV yield.

I haven't used any grid power since January 9th when the clouds finally blew out of here with the cold temps, some days -25°F. Once the snow stayed on the ground, I've been pulling in some pretty good yields on the sunniest days. My panels tilted to 65° combined with the snow really work well. On Jan 15th, my house loads were 37Kwh and it charged the battery 25.1Kwh. That is from 8.4Kwh of array.

I've been running the heat pump and radiant heaters in the house for dump loads. I keep track of sun forecast several days ahead and plan accordingly. I can turn the heat pump on/off remotely, once battery hits over 75% and the sun is shining, the dump loads get turned on.

Cold weather like this is much better for solar production than the warmer temps we had in December with endless cloudy weeks.

I prefer choices when it comes to heat. Currently collecting everything to install a gasification boiler with 1070 gallons minimum of thermal storage and radiant floor heat. (2 year project) I'll be installing another mini split heat pump this year, plus adding some PV for the house. I'm waiting to see how much propane we use by spring in the high efficiency furnace. As I said, I like choices.

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I'm envious! I know a major part of my problem is the near flat roof on the shop but I'm just going to have to live with it. I'm not putting them on the house and there's no good place to put a ground array. I've kicked around putting up something in the pasture behind the house between us and the nearest neighbor but I'll need to upgrade inverters so I could go with higher voltage. It would probably be a 200' run. I've been thinking more about it and it would let me have an array tilted to capture optimum during the winter, which would be a plus. But frankly, when it was coldest here it was cloudy as well so it still wouldn't have been enough. I'll just keep working on it. As my wife says on a frequent basis, whatever we have is a lot more than anyone we know (excluding all y'all on here, of course.)

Northern New England

The cold here has not been bad at all. The whole winter has been far warmer than normal until this week. Now we are having normal cold weather. Average daytime temperatures here would be in the upper 20sF and single numbers above 0F at night. The weatherman likes to make it sound like we are all going to freeze to death.

I installed an outdoor wood boiler in 1995 and it heats 3 buildings. I burn 20 to 30+ cords of wood a year. That is full cords, about 2 tons of dry wood per cord. I keep my house at 72F and sometimes I turn it up to 74 or 76F if I feel like it and I don't feel guilty. The boiler works great. I do lose a fair amount of heat into the ground because of the fairly long runs to the buildings and in 1995 the pipe insulation was not as good. I don't pay for wood so I don't care if I burn an extra 10 or 20% per year. I don't have to process the wood so I save all that time in cutting and splitting. The firebox is 4 feet deep, about 3 feet wide and about 3.5 feet high. I generally add wood once per day. Remove some ashes once a month. Clean out chimney once a year (5 minutes).

I have a 100,000+BTU pellet stove heating a 4th building. It works good but requires frequent cleaning to maintain reliable operation. I probably would not do this again due to the frequent cleaning.

I would say, get a chainsaw. Cut down those trees shading your solar panels and throw them in the wood stove. It is hard to beat wood heat.

Well, I cleared 25% of my panels. The extention I was planning to use didn't work out. (Bad planning on my part)
But, the sun came out and cleared another 50%.
And I'm making 3kw , until the sun hides behind the hillside. (In about 10 minutes lol)
But, I'm ready for the weekend.
Also shoveled both driveways.

EastTexCowboy said:

I've looked at those as well, along with the wood fired boilers. I don't think that's a route we want to go but I've thought about buying one and sticking it back. The biggest complaint I've seen in reviews is the volume of wood required, but maybe they have improved the efficiency. I may take another look. Typically we don't get that much below freezing days but these last 3 years have been atypical for sure.

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I posted about a portable diesel heater in the offgrid sub forum. Seems like some others have some threads on them also
8k btu that will run 12hrs on 5l of diesel isn’t too shabby as a backup/supplement in a pinch

labeeman said:

I cover all around and it has helped a lot in not having to drain the pipes as they never freeze now. You may be closer to me than that as I am only a mile from the parish line.

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Mine didn't freeze this year so far, but when we hit 17° a couple of years ago the main service into my house froze. It didn't break anything, but I had to defrost it with heat to get the water back on.

Craziest weather in central California. Lots of clouds, low precipitation, cold but not freezing. Low solar output. Utilities making bank. My highest utility bill since my install, $93

Well so far…18 inches snow …..down to 2F tonite…between 0 and 5 ( the high) the next day or two……. wind will be rather brutal till Sunday ….20 to 30 mph….…..

But on a more cheerful note …all chores are done , 70;F in the Rv …55 F in the solar trailer .panels are scraped clean for Sundays bright sun with zero temps
….both feral cats and the possum that live under the RV have plenty of food. ..and I have plenty of beer and a thick ribeye…
So all is good here…
It takes very little to be happy in life when you get right down to it…

J.

Last full charge 507 hours (21 days) ago.

EastTexCowboy said:

I'm envious! I know a major part of my problem is the near flat roof on the shop but I'm just going to have to live with it. I'm not putting them on the house and there's no good place to put a ground array. I've kicked around putting up something in the pasture behind the house between us and the nearest neighbor but I'll need to upgrade inverters so I could go with higher voltage. It would probably be a 200' run. I've been thinking more about it and it would let me have an array tilted to capture optimum during the winter, which would be a plus. But frankly, when it was coldest here it was cloudy as well so it still wouldn't have been enough. I'll just keep working on it. As my wife says on a frequent basis, whatever we have is a lot more than anyone we know (excluding all y'all on here, of course.)

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I'm running out of perfect locations in the yard, plus the ground mounts eat up real estate. The solution is taller arrays. That was one issue with using Sinclair, it ends up needing more length.

The used MT Solar mounts I hauled home had 5 panels high in landscape pattern. Rails are 17 feet and the 40 inch wide panels on the pallet just might fit but with 3 to 4 feet of ground clearance, the top of the array was almost as tall as the 60x80 storage shed it will sit by. I'm cutting the rails down to fit 4 panels tall in landscape.

No way I'm doing roof mount here. In my next video I'll show some fixed ground mounts here and how well the snow clears off since the blizzard last Saturday. Might be awhile before release, with cold temps that snow isn't leaving those panels.

EastTexCowboy said:

For me, the most important lesson was this. Without a separate heating source, and if you're in a climate where temps drop below freezing for multiple days, you are not going to be able to sustain the same level of comfort with solar alone. I mean you can, but the cost of panels and batteries and the associated support for those is going to be hard to justify for simply covering needs for a few days a year. If you're in a cold climate you probably already have a different heat source. If you're in a more temperate climate you may want to consider one. This should be especially important to newbies, reinforcing that you should be realistic in expectations and plan accordingly. Even with lowered thermostats and other reductions in use you may run out of battery fairly quickly. Of course, there are many factors and my example is likely not typical so there's that. Heating a 1200 sq ft home with good insulation, high effieciency heat pumps, and proper management would be much more doable.

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My two EG4 24K units and the 12K Senville did great, I have never had enough battery to make it through the entire night. My Mr Heater propane is a life saver on extremely cold mornings. My water froze for a couple of hours as did my mothers. Damn heat lamps burned out on each well.....replace and in a few hours they thawed out the small pipe the switch is connected to. Have a few bottle top propane heaters to place in the well house if all Letric goes away.

I just remembered why I don't want to move back to the Piedmont area.

Zwy said:

I'm running out of perfect locations in the yard, plus the ground mounts eat up real estate. The solution is taller arrays. That was one issue with using Sinclair, it ends up needing more length.

The used MT Solar mounts I hauled home had 5 panels high in landscape pattern. Rails are 17 feet and the 40 inch wide panels on the pallet just might fit but with 3 to 4 feet of ground clearance, the top of the array was almost as tall as the 60x80 storage shed it will sit by. I'm cutting the rails down to fit 4 panels tall in landscape.

No way I'm doing roof mount here. In my next video I'll show some fixed ground mounts here and how well the snow clears off since the blizzard last Saturday. Might be awhile before release, with cold temps that snow isn't leaving those panels.

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I think it's worth more investigating on my end. It would solve more than one problem.

My house roof is close to a 12/12 pitch. I wouldn't go roof mount on the house anyway but definitely not on that.

Didn't you run something like 400' to your panels? Or am I thinking of someone else?

EastTexCowboy said:

but I'll need to upgrade inverters so I could go with higher voltage. It would probably be a 200' run. I've been thinking more about it and it would let me have an array tilted to capture optimum during the winter, which would be a plus. But frankly, when it was coldest here it was cloudy as well so it still wouldn't have been enough. I'll just keep working on it

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I have the same issue coming up with plans for PV expansion, 400 feet away, ground mount, my inverters are not high PV voltage DC - BUT WAIT!
as one of the guys pointed out for me, there is no need to change inverters, you can just add a high voltage SCC for the new array and leave the rest of the system alone.
Ditto on more battery, I got mine up to 83kWh and 15 kWh on the Pacific. I got room for one more pack after that, for 114kWh ESS total, then I got to either build a new rack (and find someway to fit it in the room) or live with it like that. (OR go V2L with a Ford Lightning?)

I find it a bit funny reading all the comments on 'cold weather' - sorry, can't help myself. I had a remote site trip Jan5-16 and it was - 49C (-56F) at that site, and windy. Arrived back to the homestead to -28C (-19F) which seemed pretty nice to me. Nothing froze here, but we are set up for real winter - even @upnorthandpersonal at 63-degrees North is milder weather than NW Ontario at 49 degrees North, but we get more solar!
We ditched the Propane 20 years ago, and heat the house and shop with wood we process ourselves. For my back up system we have a pellet furnace (not pellet stove) and the back-back-up is a chinese diesel heater if all else were to fail somehow. Our wood heat needs recirculation and we rely on the solar/batteries for this. Nov-Dec I needed the utility to prop-up the solar collected each day - especially during that two weeks of cloudy weather you guys all had too. Since Jan 15 we are back on the positive side, solar collected runs all the loads except EV charging.
I am going to add a ducted minisplit for the summer and shoulder (spring/fall) seasons, you guys have convienced me!