-25F or colder?..i know my brother was up ice fishing in International Falls, mn and was out on a sled in -35F or so and got frost bite on his face…A lot of times with such cold temps its because of calm/clear conditions…which when you are sitting still isn’t so bad if you are dressed for it. The positive of such air is that its usually sunny.
Wow, if we kept the heat at 70, our bill would be outrageous. We have an all electric house, including the heat/AC, run thru below-floor ducts. We have no back up heating arrangement, but my wife would like to add wood heat. But, our home is too small to put any kind of wood stove in. I would prefer a small propane wall heater, but our insurance wouldn’t cover that or wood heat (we live in a large single wide).
We have also considered a wood boiler, but they are quite expensive. Still not ruling one out though. They are widely used in these parts.
You still have to wear a sweater, shirt and thermals even with the heat at 80? Or were you wearing that when you used more heating oil?
Is that $460 a monthly electric bill, or total winter bill?
Might get a few flurries Thu morning, first of the season. Supposed to be about 20 Fri and 17 Sat morn, coldest so far this fall. Not looking forward to the cold, but it is time for it.
We’ve paid $460 over the last 12 months for electricity, not monthly. And that is with the higher temps. But, we spent a lot on the solar panels…
No, if it was 80F everywhere I wouldn’t wear them. But if I am going back and forth between 68 and 80, I’m fine with keeping bundled up. Better than taking some off and getting cold when I go in the other room.
How new is your AC unit? If it is getting to be close to end of life, you could replace it with a heat pump. Our AC was very old and 2 of 3 units didn’t work for some time- I went 2 summers without any AC at night. I found 90-95 uncomfortable for sleeping, but it was fine if I opened windows and used a fan for a few hours before bed to get it down to 85. But when the 2nd unit went, it seemed like a good idea to get replacements. It worked out nicely to get heat pumps instead of normal AC, as we could then use some of the electricity the panels generate for heating as well as cooling.
Keep in mind that if you use “normal” (resistive) electric heat, the amount of warmth you generate is 100% of the energy you put in. But, with heat pumps, you get more than you pay for (a rare thing in life 
). The COP (coefficient of performance) is usually somewhere between 2 and 4, meaning that you get 2x to 4x as much heat as you use in electricity. The COP changes, depending on the temp (I think mine is rated to ~2.5 at 17F and ~3.5 at 47F). This is because it gets harder to extract heat out of the air when the air is colder. I could have gotten a higher COP, but the cost of the installation goes up pretty quick.
I use a “air source” heat pump, which is much cheaper than “ground source”. But the trade-off is that GS would would better in cold weather because the ground doesn’t get as cold as the air. It does cost a lot more to install though, as it involves drilling and running pipes into the yard.
Wow, $460 is great for a year. You might have mentioned in another thread how much you paid for the solar system, but what was your total outlay for everything? You must use a lot of panels to be able power your big house. I imagine you have to have inverters and battery backups along with the panels? When do you think y’all will reach the break even point? I’ve heard most home systems pay for themselves in about 10-15 years?
Right before we left TX, I worked at a power supply/backup plant. They were just getting into solar systems and I asked for a ballpark price for our house here, and it would run at a minimum of about $10k.
As mentioned, we also looked into wood boilers, but those were running about $5k for the unit and installation. But boilers aren’t real efficient, unless you get one of the newer units that run at much higher temps. They recirculate the exhaust gases and burn those at much higher temps so that there’s not as much waste.
Our outside unit is for AC only, it was installed I guess 13 years ago when my wife had this place built. I imagine we have resistive heat, so not too efficient. If I remember correctly, the outside unit at our place in Texas did heat and cooling, so I guess that was a heat pump?
Hi Bob. I’m with you on heat pumps. We installed a ground source “pump & dump” (open loop) GSHP about 10 years ago. Open loop is not an ideal configuration in our situation, but all told it has worked pretty well. We only have to pump water about 60 feet, and we then discharge it into a sump. We’re very lucky that we’re able to do that, as laying pipe for a closed loop, or drilling additional wells, would have been prohibitive at best. We’re also able to use the same well/pump for irrigation, which in itself paid for the system in just a few years.
We live in an older home and were able to use the existing ductwork (not perfect, but useable) so that mattered. The system replaced a gas, forced-air system, which in retrospect would probably have been good to stay with given the drop in NG prices, but then we wouldn’t have had the irrigation advantage. So all in all, it has worked out pretty well
A lot of factors to consider, though!
-8F here right now and likely to get down to -13F or so overnight. Coldest night in a couple of years. It was cloudy/misty/snowy all day, not much solar gain. Wood fire has been going in the wood stove for 1.5 days now.
Being out in the cold isn’t too bad if you are dressed for it. Bright sun does help A LOT when you have it. Still it’s hard to get much done at these temps when you fingers go numb after 10-15 mins or so without gloves on.
Fortunately I did get the last of my garlic planted last weekend, when it was still above freezing the ground could be dug.
On the other hand, I was amazed that our chickens choose to stay out in this weather until it got dark especially with snow on the ground so they did not have much to peck at. (then they headed into the heated coop for the night).
1 Like
I had thought that I put the info in this thread, but it looks like I put it in another one recently, when Patty mentioned considering getting solar. We needed 33 panels and it cost $54.5K, before tax credits, etc cut it almost in half. I don’t think that all the credits apply anymore though, as some of them were being phased out when we got it. I think once something starts to make sense, the incentives get taken away…
http://www.growingfruit.org/t/what-state-has-the-cheapest-property-tax/7997/39
Two Sunnyboy 6000 inverters were included in the installation. One nice feature of them is that when the grid power is out you can put them into local-supply mode. Then, they can can supply 2 plugs, with a total of 15 amps of power (for each inverter). Of course, in the year and a half since we got the panels, we haven’t had a outage to test the feature in. Not that I want any outages…
If I wanted to be off-grid, then I would need a lot of batteries. But, they are pricey and I didn’t want to pay 8-10K for that feature. A key part of the ROI for solar is “net metering”, where the meter rolls back when you supply power to the grid. You effectively bank electricity, so that you can use it at night and during the winter.
It works fine now, when not many people have solar, but there is a problem if everyone has solar panels. If that happens, then the electric company would need to deal with a lot of incoming during the day and a lot of generation at night, all for everyone paying almost nothing (just connectivity, $19.25/month for us). Surge generation is generally more pricey than base generation, so that would be a nightmare for utilities. I suppose that two possibilities would be storing the energy (molten salt is a possibility), or sending it a long distance to a longitude where it is dark, both of which have some issues.
So it is understandable that utilities would push back against “net metering”. I think in at least one state (Arizona), new installations won’t be able to get the full credit for energy supplied to the grid. While I see the utilities position on the issue, I think it is probably more important in the long term to build our solar capacity (similar to Germany).
According to the sales guy, the payback is 8 years. But, he used some “beneficial assumptions” (as he is a sales guy). I think the biggest one is that the cost of electricity will go up at a steep rate. The projection lists it as $0.18 per kwh two years ago and $0.27 in year #8, but saw $0.16 when I looked a few days ago, so that hasn’t come to pass. My best guess is that it will pay for itself in 11-12 years.
Yup, a heat pump is just a reversible air conditioner. So, whenever you want/need a new AC, just get a HP and it can help with heating. It’s probably more expensive than AC, but it may not be prohibitive. We paid 18K for 3 3-ton units, including new air handlers (a part you may be able to avoid if your current air-handlers use 410a instead of Freon). [quote=“marknmt, post:26, topic:8006”]
A lot of factors to consider, though!
[/quote]
Yup, I’ve spent a decent amount of time looking into this stuff (solar, heat pumps, etc) in the last few years. But, I do find it interesting, as evidenced by my way-too-long post.
One other factor I was worried about with heat pumps was that since I’m taking energy out of the air, I’m effectively making pockets of colder air outside. Normal people won’t care about that, but I’d hate to kill a persimmon tree with a burst of icy air when the temp is 5F outside or kill some plum flowers in April on a night with 28F temps, where my HP makes it 20F instead.
Best I could do was to position the heat pumps in a location between the driveway and the house, where heat tends to accumulate due to exposure to the S. That will tend to make it a bit tougher for AC in the summer (pushing heat into a warmer area), but we don’t use that much AC anyway, so it wasn’t as big a concern. It also gives it a decent amount of distance to the nearest fruit trees, as it has to cross the entire driveway (3 garages distance), over which it should hopefully diffuse somewhat. If worst comes to worse, I can switch over to oil on unseasonably cold spring nights, as I think I did once or twice this past April.
2 Likes
A lot to be worked out yet, (many a slip twixt the cup and the lip) but with the advent of electric cars there is about to be a lot of night-time storage capacity sitting idle …
Just a thought, and not, I’m sad to say, mine, as I got it from an engineer that used to participate in another board I liked.
Incidentally, and just FWIW, we’ve yet to need the electric backup for our system, although one year we did run the heat pump around the clock for the month of February, and by the end of the month the temperature in the house was starting to drop a hair every day. March came just in time! I think the system might have benefited from being sized up a bit more, but all in all it’s been good.
I think the best energy-saving investment a person can make is in insulation and weather sealing. But once you’ve optimized that go for the most cost-effective HVAC you can get.
4 Likes
Nice being down here at 30N latitude. On any sunny day my 180 sq ft sunroom heats my 1100 sq ft house to 80+F. It will do that when it’s 40F outside. On 60F days I have to vent off excess heat.
In addition last winter I grew several thousand dollars worth of fig plants sold on Ebay.
The sunroom cost about $300 to build and saves several times that in heating cost each yr. I only need to run the furnace on cloudy days. It won’t work tomorrow at 33F high and cloudy.
3 Likes
Ditto that @fruitnut. In a sunny climate it’s hard to beat free heat from the sun. Even in my relatively cold climate, it can be 10F outside but if its sunny no need for a fire until an hour or two after sunset. That from some strategically placed S facing windows and good insulation. (Or course you’ll want to design your overhang so that summer sun does not make it to those windows).
A lot can be done in terms of heating/cooling a home with a bit of clever planning and design.
1 Like
It doesn’t even need to be very clever here. After a very cold night when the house drops to 50F my sunroom will heat the house up nearly as fast as the gas furnace. Still with all that free heat there are only a few passive solar homes. And I don’t know of another collecting solar heat like I do.
I’m getting older and haven’t let the house get that cold in a couple of yrs. What that’s done is give me excess heat. I can’t stand letting the house get above 86F. So many days I need 50% shade cloth on the south side of the sunroom. I could just close the door to the sunroom. But then I’d cook my plants. It can hit 130F many winter days unless I bleed off heat into the house or do something else.
2 Likes
Thanks Bob for the generous response. So during the day you have enough power generation thru the panels and inverters to run everything in the house (or almost everything), including the heat pumps, and if necessary, the boiler? I was wondering what the kVa rating is on your system. What is the impact of an overcast day as opposed to a sunny day, power wise? Also curious as to the useful lifespan of the panels, and do they move with the sun, are they adjustable, or just fixed to the roof?
I could see how you save lots on your electricity bill- during the day, it’s all solar, and like you said you put your excess juice back on the grid. And, at night it’s just normal electrical use. So, the net usage is almost zero. Of course, this time of the year I guess you have to pay a bit more due to shorter, colder days and naturally cloudy skies.
I just checked our provider’s usage rates, and it runs about 8.4¢/kWh, which is very reasonable. We belong to a cooperative, which usually means lower rates. We belonged to one in TX, and our rate was about 12-15¢, whereas the big providers would get you for about 20¢. What I don’t like here is they slap an “environmental surcharge” on our bill, that has been as high as 15% any given month. Guess they gig us for still using coal powered plants. Our line usage fee is $15/mo, I think, and we pay about $9/mo for a high pressure sodium pole light.
Our co-op has some different plans one can use depending on your usage. One is called a fixed usage plan, where if you can keep your usage <700 kWh a month, your rate is only about 6¢, but once it gets above that it’s like 12¢ or so. So, in the spring and fall, it’s worth it, but not in the summer, and def not in the winter. They also have a plan where they charge much lower rates on off peak hours, as opposed to high peak. Y’all might have similar plans, I don’t know.
BTW, I think our highest usage month was in Feb-Mar of 2015, when we had a very cold period, with a few nights below zero, and lots of snow on the ground. I think we used about 2100kWh! Our bill ran about $220, I believe, even with the thermostat set at about 64.
1 Like
Our low for the week is10 degrees F and highs are 35. Weather is very good for this time of the year.
During the day, I generate way more than I use, since I build up a lot of “credit” through net metering. But, I don’t think I could run the whole house on the 2 plugs (per inverter, 4 total), as that is a limit of 3 KW, far below the max output of the panels.
I don’t see that metric anywhere in the literature. But, I’m guessing that you mean the Watts (VA → VoltsAmps → Watts). The panels total 10791 Watts (32733), but actually exceed that sometimes. The efficiency of the inverters is supposed to be around 95%. On a sunny late March day (panels are more efficient at lower temps and temps can get pretty high on the roof), I sometimes max out the inverters, generating 5.5KW from each.
Quite a range…Month of November:
From the brochure:
Just fixed. I happen to have a decent amount of roof with a good South facing orientation. The snow slides off them as well- just have to be careful to not stand under it the morning after a storm.
Nope, I’m still on $19 bills, as I’m using up the net metering from summer. It won’t be until Jan or Feb when I start to run short. Not too bad, as every March it resets anyway. At that point, they pay you for whatever is left, but only at wholesale generation rate (I was told about 1/3 of the normal cost).
Ouch, 10F is pretty cold for now. I think we’ve seen 22-23F, but most of the nights are still in the high 20’s or above freezing. I’m still putting my figs to sleep, something I’m hoping to get done before we get below 20.
3 Likes
I have a outside wood boiler and I wouldn’t be without it. I heat my house 2000 Sq ft. upstairs as 2000 down, I heat my shed and it makes my domestic hot water, which means when I come in the house after being out in the cold all day, I can take as long of a hot shower as I like. You just have to watch which brand you get, as some can burn a huge amount of wood. I use about 10 ranks per year, and my wife likes the house at 75 degrees, so for me the wood boiler is great.
1 Like
That sounds pretty nice and I’d love to have one, but how did you do it for $300? Just replacing a single window is around $200 (when you shop around and do a bunch of them) and a sun room needs a frame, foundation, and lots of windows.
I’ve thought about adding one (or a full greenhouse) but had trouble justifying it to myself (let alone my wife). Also, the way my house is situated, there isn’t any South facing area that doesn’t have a driveway or deck (10ft high) in front of it. I suppose I could build a two story one and enclose the deck, but I think that would be even bigger $$.
I’d say that’s a good thing. I wish I had little less “insulation”!
But yea, I hope everyone makes it ok. I’ve never, ever seen weather like we’ve had here on the KY/TN border. It is in no way an exaggeration to say that we haven’t had a handful of days below FIFTY degrees until this week! For December, that is just crazy. My understanding of chill hours is that they don’t much count until the mid to low 40’s, so if that is true, this might be a really interesting year for my trees since they would normal have accumulated a LOT my chill hours by now. Perhaps that means my trees won’t come up of dormancy as early this year-which could be a blessing for things like my apricots. We shall see. I have one sweet cherry tree (Tulare) which has completely lost its “mind” and broken into full bloom and sent out new leaves- lots of them. I’ve seen an odd bloom or two appear at strange times, but this is most of the tree! Interested to see what happens.
Good luck to everyone with the pending cold. I tend to hold my breath all winter with fingers crossed that I don’t loose my peach buds as I have in the past.
By the way, @BobVance and others, I just want to say that this has been one of my favorite threads in a long time- extremely interesting and informative. I somehow was unaware that you (Bob) had a solar set-up. I’ve always been interested in the concept but have never taken the time and effort to really do the in-depth research needed to determine whether it would be worth while for me. In one of my barns that I rarely go in at night I have a very simple little solar panel hooked to a battery and a light. Everytime I use that light, I just love the feeling that I’m getting something for free. Of course I had to buy all the stuff and the batter won’t last forever, but still, it feels like “free” energy and I just love the idea. On the same lines, I go to Mexico quite a bit and down there most houses have a big water tank on the roof painted black to provide hot water-probably the most elementary but effective “solar” heat that exists, and I love the idea of that too. So, for me, doing my whole house would be much more about the financial benefits than the environmental ones, and it sounds like that was the primary motivator for you too (though I’m sure you feel better not using fossil fuels as much). I’ve never been completely certain whether it would financially be beneficial, and some of the government publication I get at work indicate that many states and local utilities are cutting way back on the tax benefits/breaks that solar used to come with (as you mentioned). So I wondered if its still a great idea to go solar.
Anyway, thanks again for taking the time to post such useful information, and thanks to @subdood_ky_z6b for asking such great questions- almost every one of yours were the same ones I had. It’s also nice to see Bob give me a run for my money in terms of lengthy posts! haha. Difference is, yours were full of good information while mine tend to just be my ramblings. Speaking of which, I should stop now. Thanks again, everyone, for a great thread!
1 Like
About 10 years ago we had a cold winter and it was -6 F this time of year. It was so cold that year It was record cold. That was real temperature not including windshield. December is much warmer than January!
It’s a nice benefit, but your right- I wouldn’t install them if it wasn’t at least on par. The way I see it, solar is close enough financially and protects me on the upside, if electricity increases. Also, once the panels reach payback, they should still have another 15+ years of giving me “free” electricity.
The below article mentions that it has been hard to get panel recycling started, since so many of the old panels are still in use, saying “We have product that’s still performing to standard from 1978, so we don’t have a big stream.” So maybe the panels will last for another 25+ years after reaching payback. That’s a lot of savings, though who knows if I’ll be in the house that long- I would guess not, but who knows. Even if I’m not, it should be a value add when selling.
Another aspect is that using solar isn’t cutting out all pollutants & CO2. A lot goes into making them, as the below article mentions. Though I was happy to find out that my manufacturer ranked 2nd of 31 makers. I bought from them because with their high efficiency I could supply enough electricity in the optimally angled part of the roof, rather than needing to take some that faced E or W (with good S exposure still).
1 Like