Solar Back-Up power project
I tested the new inverter yesterday, after checking out the guts..
http://i46.photobucket.com/albums/f1...ranformers.jpg Hooked it up to the 48V bank and ran it while charger was running. It came with some short cables. http://i46.photobucket.com/albums/f1...Solar/z032.jpg In the evening, when there was no more solar, I decided to run the bank down a little bit, and test the inverter at the same time. I ran the inverter for about 6 hours, using incandescent bulbs as loads. Using 200 to 300 watts, while watching the bank voltage closely. Under load, (at 14:30) the bank started at off at 50.7 volts. (12.675 per battery). My target voltage was 49.5v, (12.375v per) which we hit at 20:30. I think that 12.375 is about 70 to 80% of a full charge. (See chart below). This morning started off real hazy and got better around 10AM. A little after lunch, the TS-45 charger & 500w of tracker PV had re-charged the bank to the tune of about 21.6 amp hours. This afternoon, I tested the inverter with a computer and CRT and they worked fine. At the end of the day, I checked the battery under load and it was 52.0v (13v per). I think this higher voltage is due to the temperature compensation function. Which increases the voltage slightly during the different charge modes. It's under 55 deg F in my basement.. I never saw the charge state go into 'Float' mode, but the charge current dropped from 7A (Bulk mode) in the morning, down to 2A at 13:00 (Absorption mode). But, So far, I'm pleased with performance of the charger and PV. I might have to adjust the temperature compensation off-set, after I take some more under-load voltage readings tonight. This chart shows how different loads affect the voltage during discharge. I was using around 4 amps. http://i148.photobucket.com/albums/s...terycharge.jpg |
Power source is 500w of tracking PV array
http://i46.photobucket.com/albums/f1...Solar/z008.jpg Charge controller is a TS-45 (PWM) http://i46.photobucket.com/albums/f1...olar/wired.jpg Bank is 48v of Marine batteries from AutoZone http://i46.photobucket.com/albums/f1...Solar/z077.jpg http://i46.photobucket.com/albums/f1...Solar/z080.jpg Inverter is 2.5kW MSW. (48v DC input 120VAC out). http://img.diytrade.com/cdimg/131563...Wave_2500W.jpg Wholesale 2500W/5000W POWER INVERTER STACKABLE DC 12V TO AC 110V |
Plan 'A'
http://callaway.org/shares/IMG_3761.jpg
I plan to do my layout kinda like this, but I'll keep the inverter over near the battery bank, since it needs very fat wires (high amperage). That way, I can install a small Aux breaker box and use the breakers as the inverter AC cut-offs, and also control which (of 3) household AC branches are going to be fed by the Inverter. MSW voltage isn't suitable for some loads.. :o |
Woo, looking good so far. :)
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While the PV was charging the battery bank this morning, I turned on the MSW inverter, and tested it on a few things in the basement.
1. 1/3 HP Ace sump pump (short test, no water) 2. Large Craftsman power drill (360w) 3. Ceramic space heat (at 952w) 4. Small basement freezer (180w intermittently for 3 hours) I had a 100watt flood lamp plugged in while I was running these tests, and didn't see any dimming at all. The solar charge controller did it's work earlier this morning and has been in 'Float' mode. All the juice for the testing is extra PV power that wasn't being used.. (So, I didn't waste any power).. :) It looks like the inverter uses very little power in standby mode. (Without loads). I think it's less than 5W. Will have to use a real amp meter to tell for sure. |
One of the main goals of this back-up system is to provide 2 to 3 hours of power for four sump pumps.
Since the 4 pumps (each using about 300 watts) would start up and run at random times, with about 30 seconds to 1 minute of run time, per 3 to 5 minutes of Off time. It's very likely that normal flooding will cause the use of less power, than would be used by running 400 watts continuously. My guesstimate is 0.3 to 1.0 kWh being used during each hour of flooding, depending on the height of the flood-water table. (Unless we get another 100 year flood, ahead of schedule). :eek: The main load is these three new pumps and one old Ace Hardware 1/3 HP pump. http://i46.photobucket.com/albums/f1.../2newpumps.jpg http://i46.photobucket.com/albums/f147/Xringer/D004.jpg The Gray box is a SumpJet water powered sump pump. (In case everything else fails)..:( The run time of the battery bank during a flood will depend on SOC and if the sun comes out. Most of our flooding occurs 1 to 3 days after heavy rain has stopped. So, there is a possibility that battery life could be greatly extended by the PV. Which, at 300 to 500 watts could drive the pumps while simultaneously recharging the bank. ~~ The reason for the 2 to 3 hours of power as my goal is simple. In 90% of power failures during flooding, the power is quickly restored. In any kind of weather, 90% of the time, NStar has restored power in less than 3 hours. Two or three hours of a dead grid, should be plenty of time to roll the 5KW gas generator out of the garage and get it running. (Which is something that I would like to avoid if possible). But it might be unavoidable if the flooding is heavy and the battery bank falling low too fast.. Cheers, Rich |
layout work
Yesterday I worked on the layout for my board..
http://i46.photobucket.com/albums/f1...lar/layout.jpg (That little blue box on the lower left is just a place holder for metal boxes). Today fiberboard is up and ready for the boxes.. |
Started wiring
http://i46.photobucket.com/albums/f1...r/strarted.jpg
I've wired the ground and the two hot lines into the 3 switchers. The inverter will feed in to the breakers (left box), which will drive the relays. When the inverter comes on, it will disconnect my loads from the grid and feed them with juice from the inverter. |
Wow. That looks really great. But it does really look complicated too. How much did you spend to all of that? Is it less complicated to build than we see it? Hehe
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Quote:
A much simpler rig would be a GTI (Grid tied Inverter), which just connects the PV (panels) to the grid. It's a little more complicated than being off-the-grid, since it has switches to allow a few house circuits to go off the grid when needed. (At least when I finish wiring it up). :) I didn't track the price paid for parts, since I never expect to see any kind of break-even or pay-back that many people look for as the goal of getting to Alternate power sources. I'm not looking for a hand-out from the government, since the goal of this project is Back-up power. Like the gas generator in the garage. I do try to get good deals.. My panels were all about $300 each. The CS6P-200 panels are still being sold on Ebay at a good price if you can get them to accept your offer. I'll try to draw a good diagram of the system. I'll post it here. Cheers, Rich |
1 of 3
http://i46.photobucket.com/albums/f1...ockdiagram.jpg
Here's the guts of one of the three circuits. (Only #3 is wired at this time). We cut into the 120VAC house wiring, between the breaker box and the loads (outlets). The NC (normally closed) contacts allow the power to pass normally. But when the Inverter is on and the 15A breaker is closed, the relay coil is energized. The relay disconnects the loads from the main breaker box (the grid), and allows the inverter to feed those loads. I have the time delay disabled, so power from the inverter turns on the relay instantly. Here's what it looked like before the blizzard of 2011 hit us. http://i46.photobucket.com/albums/f1...olar/panel.jpg #3 box is finished.. But, the AC input from the inverter has not been wired into the little breaker box yet. The inverter (and bank box) have not been moved into their final resting place yet. I will likely use a 20' extension cord for testing.. |
Filter check
I installed a filter inside the breaker box.
http://i46.photobucket.com/albums/f1...Solar/z035.jpg "XPF 20A Wired-In Noise Filter" XPF 20A Wired-In Noise Filter - X10 Pro I want to see if the squarewave-like MSW waveform can be cleaned up a bit. Maybe round off the sharp edges a bit.. I ran my 200w computer room load for a while and didn't hear any buzzing. But I did hear buzz when I got close to the filter. Those iron cores are singing. When the sun comes back out again (maybe Friday), I'll crank it up again and see what the line looks like with the O-scope.. Neat thing happened. When I shut off the MSW inverter, the relay dropped out, and re-connected the grid to my PC.. Did not re-boot! And drop-out is a lot slower than energizing the relay (turning on the inverter). Edit: 3/2/2011 The filter buzzed a little, and didn't round of the shoulders of the MSW very much. Then, I saw it was loading down the inverter! The output of the inverter supplies the breakers. With all the breakers open, I should have had about 70 ma of DC inverter load.. But, it was closer to 200 ma of DC current. I assume the high frequency component of the waveform was seeing the caps as a load. So, the filter is out of the box.. My plan is to try a large DIY iron-core inductor in series with the inverter AC output. It will be made from about 10 feet of #10 wire, coiled around a one pound iron rod. (or maybe mild steel). :p |
sweet. Mind if I ask what this has run you? My constantly wasted 45 watts of panels would make me much happier if they charged a battery bank then the excess went to keeping a PC or the woodstove fan going.
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I don't keep track of what I spend on this stuff. It's not like I'm going to get a tax break on a back-up power supply. ;)
But, you can Google the hardware and see who has the best prices.. If it's only 45w of PV, you should find a cheap charge controller and get a good battery, and use that stored juice at night to run 20-30 watts of LED lighting. I've got two 10W panels and finally put one of them to work running the LED reading lamp on headboard in the master bedroom. It's nice because it can run for days without sun. And if we have a power failure, I want a good light working when I get out of bed. (and need to find my flashlights)! I have not decided what to do with the second 10w unit, but I'm leaning towards 5 or 10w LED lamp in the kitchen. |
Ready for the next storm!
Got them dug out and tweaked the up angle on the tracker. The sun is higher in the sky!!! :thumbup:
http://i46.photobucket.com/albums/f1...hoveledout.jpg I now have a little path dug down to the panels. Still need the tall boots, but now it doesn't take five minutes to slog though waist deep snow with a crust on top.. Yesterday, I got out there early and freed up the bottom panel on the tracker. When the ice broke, it buzzed and started moving west! I got there just in time! I'm not sure if the motor could have broken it free.. So, now we ready for another foot. But not two feet! :eek: Loads of sun today. Some of hotwater heating from the 400w fixed full bank charge from the 500w tracker.. |
Sunny yesterday and today!
Yesterday, I used the MSW inverter with the batteries/tracker to run my PC and some other loads for about 8 hours.
In the evening, I still had about 12.75v(51v bank) on the batteries (no load). When the sun came out fully this morning, my 500w tracking array was providing a full 500w of charging power into the bank (Bulk mode). Which kinda makes me glad that I didn't spring for the MPPT charge controller. :p Also checked on the Canadian twins, and they were pushing 412 watts into my hotwater storage.. :) Which I think is pretty dang good for early morning sun, on a non-tracking array.. |
Dump Load controller
I built a small voltage sensor (12V) that will control an SSR, that controls the AC from the MSW inverter, to the load.
This should keep the inverter from discharging the bank below 48v.. I hope. I'll be testing and tweaking this week. The board is on the lower left. The SSR tray is upper right. http://i46.photobucket.com/albums/f1...Solar/z206.jpg Wide view http://i46.photobucket.com/albums/f1...Solar/z203.jpg |
How much power are you getting out of these panels on a regular/average basis?
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Since the weather has been pretty irregular lately, I don't even try to use the
backup system most of the time. Now that it's getting sunnier, I've started using it to run my PC load (about 300w) until the sun goes down. It's been on since I came home from work today (16:30) and I'm going to see when the little circuit starts trying to turn off this evening.. (If it does).. I'm not sure that I want to start logging the kwh numbers, since it's not what I consider a good use of my spare time.. I've met my goal of creating a back-up supply that we can use during power failures. I plan to use it lightly, just to keep the batteries in good shape. Make them last a while. However, I don't like the idea of 500w of PV going to waste after the bank is charged.. So, I'm thinking of adding a 230vac inverter and running the Sanyo when the bank is already charged. Backed-up AC would be nice if the grid fails on a hot day this summer. I can stay cool using the tracking array.. 500w will do the trick! :D |
Very interesting project! I will be grid connected, but I intend to eventually have a battery backup for several reasons.
One of them being that in case of a blackout, the inverter shuts down and PV production idles. This is where I can continue to use the DC directly to charge a set of batteries. Off these batteries I will run a USB bus, as well as 6, 12 and 24 volt. This enables me to run all these small DC gadgets directly, without using the supplied AC-DC power supplies for each unit - that is, without making solar PV DC into AC, then back into DC. The bus WILL run all the time, but normally it will be solar/grid powered, whereas during a blackout, it would be solar/battery powered. If the main AC grid has a blackout, the inverter will have to shut down. If not, it would try to run the entire neighborhood electricity use, which is not possible - the inverter would snap instantly! So when a mains AC fault is detected, the inverter will switch to local mode (by a control system I will design - it is not that complicated really). Because of the inverter built-in protection logic, I need an AC current it can sync against. This is where a small battery operated inverter will feed a lead AC into the inverter (instead of the mains AC), to keep it running. It will still need some further protection circuits, to make sure that demand does not exceed production. Since the battery pack will only supple the small controlling inverter and not the big one, the main AC users cannot be used when there is no sunlight. But the small inverter will keep the solar heat pumps and control running, as well as other essential - but low power - units. Maybe including the TV? :) So the two main reasons for me to extend to battery backup are 1) To get the solar PV DC production directly into local DC gadgets, without going DC->AC->DC and 2) To be able to sustain PV usage in the case of a grid blackout Would I not feel stupid, if there was a blackout and my PVs cannot be used! That defeats the idea of producing your own electricity! |
I use a MSW inverter that can produce 2.5kw (5kw peak, 120vac).
I've tested it with a 1500w space heater , and the inverter heat sink doesn't even get warm. I have to conclude is unit is very efficiently turning DC into AC. So, instead of trying to make AC loads work off DC, I'm just going to use AC. I'm also thinking buying a 230vac MSW inverter (48dc input) to use with my solar+bank for powering my Sanyo AC heatpump. I might be able to charge up the bank and cool (or heat) my home at the same time. Depending on the sun.. :) |
New Inverter
I impulsively placed a bid ($250) on a new inverter..
I've decided that we need another inverter (with real sine waves) to power the main downstairs AC circuit. (The FIOS box, backup PC workstations, freezer and new dehumidifier). The new dehumidifier will run on the old MSW inverter, but makes a noise like a buzz saw. And that can't be good. :o Anyways, this PowerJack was the only one that I could find that used 48vdc in this power and price range. They have some 12vdc 1.5kw units, but these 48vdc units are hard to find right now. They billed me for it, I hope they can make one (in China) and get mailed out before fall.. I was just thinking, my old 1200w GTI powerjack will be able to piggyback on top of this new Sinewaver. :D Just in case 800w of PV (+battery bank) isn't enough for the daytime load. I could wire in an extra 500w of PV from the tracker array for a total of 1.3kw. http://12vgridtiepowerinverters.com/...0625229557.jpg 1500W pure sine wave power inverter 48V/110V Dc to AC 1500w pure sine wave power inverter This is a 48volt DC to 110volt AC power inverter with 1500 watts continuous power handling and 3000 Watts peak power, pure sine wave, thermal shutdown, reverse polarity protection, low voltage shutdown, low voltage alarm, specification Item No. PSW-1500-48-110 Continuous Output Power 1500W Max Output Power 3000W DC Input Voltage DC 48V AC Output Voltage 110VAC Regulation ±5% Frequency 60Hz±3% Efficiency 87% Output Wave Form Pure Sine Wave Input Low Voltage Protection YES Input Reverse Polarity? YES circuit protection YES Output Short Circuit Protection YES Overload Protection YES Net weight 5kgs Certificate CE |
Quote:
While I don't feel a 'breeze' inside my shed, the draft from the outside vents is significant. It makes me feel better about my property sitting in the heat/humidity of SW Texas. |
"the heat/humidity of SW Texas."
I missed the humidity of SW Texas, since I left home in 1963, just before they built a big dam on the river, just north of town. (Del Rio). I grew up in a 'dry' town, and found it very dank when I came back for visits.. But, after the sun comes out for 5 or 6 hours, it dries back up.. :D It's funny, I'm sitting here thinking about turning on the heatpump, because it's 53F here.. In the meantime, I'm dressed like it's winter, looking at the weekend forecast for Del Rio, of 103 deg F.. Dang!! :eek: That's no country for old men.. :rolleyes: Cheers, Rich |
It's here!
http://gi120.photobucket.com/groups/...0625229557.jpg The new inverter came in from China and seems to work. One of the coils inside was loose, since it was wrapped in tape before it was glued to the PCB, it didn't hold very well and (Fedex) broke the wire strap that held it down. But, that had no impact on it's operation. Testing at 40 to 600 watts is okay so far. ~~~ When I connected the new Dehumidifier to the load, the new inverter started beeping like crazy, while the display on the Kill-a-watt was blinking 800w. But, it quickly settled down and started working. I suspect this 1500w rating might be some Chinese Hype, and I should run it under 1kw. In order to run the Dehumidifier this summer, (if we actually have a summer) I'll disconnect the hot-water heating element and piggy-back the 500w tracking array into the basement load circuit. (The 500w PV will need to be rewired to series-parallel for 35vdc @14A) The old 1200w GTI AC output wired onto new 1500w true sinewave (to simulate a grid-tie) is 800w+500w (1.3kw Max) of PV. So, I should be able to run up to 1kw of AC loads and still be charging the 48v battery bank, when it's sunny. The main loads will be the Dehumidifier, the basement freezer and this PC. These loads vary a great deal, so at times of low wattage, the bank can play catch-up. I hope! |
This system is looking very complicated but your effort is really appreciated. Your information is really very useful.
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Xringer,
I wish I could come up with some earth shattering vision for you, because I've done so much reading on PV panels and PV systems. Your doing a lot of things right. My biggest help is try not to do any converting from dc to battery back to ac the loss is greater then 50%. If your building something for the end of the world scenario, don't bother. Food and water may be a better option. If your building somthing to save money, my suggestions may help. Because I reached a conclusion on this, I can tell you what I've done. 1) Best PV system, is one that tracks the sun. 2) Next best is tilt array. 3) Last - fixed tilt, depending on when you want productivity, winter, summer. I went with a tilt system where I can produce max electric, winter or summer. If my total production reduces my consumption, I feel I'm getting the most out of my pv system. Everything I generate during sun light, connected to the grid, will be subtracted from my night time use of electricity. If your thinking black-outs. You can't do it, without batteries. As you charge batteries everyday, being ready for a black-out, how many days, of being prepared, during the year are there? Sounds like a generator is a better option. Use your PV for reduces my consumption. Vern |
My (tracking) back-up system was made for a unique 2-part event.
1. Heavy rain has caused ground water to rise, which will lead to basement flooding. 2. The grid fails and I need a few hours of AC power to keep my pumps working. (I've only seen this unique event happen a few times in the last 30 years, but we just replaced the basement flooring, from the last flood). I also own a 5KW gas generator, which I can use in the case of an extended grid outage. It's not something that I would want to use during an ongoing storm. Because of the way life seems to play tricks on me, I'm pretty sure that my back-up system will never be needed during it's life-time. (or mine). :o |
Xringer,
You can move a lot of water with a pump in a short amount of time. I don't know what the in flow of water your dealing with. It sounds like your basement flooding is a random event and you need a toilet valve to turn on the ejection pump. You might rig up a light on the main floor letting you know the sump pump has been activated. A larger sump hole may allow you to run the pump once a day. Like I said I don't know what the in flow is. Once a day pump activation may be an interval you can deal with. Arizona is not a place where basements are common. Sounds like you live on a leaky boat.:rolleyes: This may be a bigger problem then what meets the eye. Just a quess... your steam wall may be leaking. Steam wall - is the concrete seam where the wall and floor meet in the basement. You may need interior drainage system that will guide the water using drainage pipes to the well (sump hole) so that the pump can pump the water out as needed. If you have no warning when the basement is going to flood. The size of the sump hole you dig must meet the intervals you check the basemant for flooding... I'm sure get the idea. Hope you can stay above water,:eek: Vern |
48 volts still there?? 10 years later?
We had a winter storm recently and lost Grid power.
I wondered if those old 12 volt car batteries (marked October 2010) still had any juice in them.?. The back-up system still works! Got some lights on and put away the flashlights. We got grid power back in about 2 hours, and the pack voltage still looked okay. Today, I checked the water level in the cells and it was fine. But I see some stuff like white power down on top of the plates. Even if they have very low usage, I have a feeling that a decade is a long time for these batteries. We How long are these old batteries going last? If we get some sun this weekend, I'll test the system battery health. I have a feeling they might need replacing. ~~~~ I'm looking at a Sine wave inverter, because we have a CPAK now and I don't want to harm it's little power supply module. Plus, we have a lot more 'devices' plugged in now. https://www.amazon.com/dp/B074BQJRFF This one: Xijia 3000W (Peak Power 6000W) Pure Sine Wave Inverter DC 48V to AC 120V 60HZ seems like it might be pretty good. Anyone have any recommendations? Thanks, Rich |
48V 1.6kWh Li-ion Power Pack??
I was wondering about my PWM charger and found this paper..
https://www.morningstarcorp.com/wp-c....-Why-PWM1.pdf It seems like I should have been 'periodically' putting a load on the system. Eat up some Ah at night, and let it charge up the next morning. That might keep the cells in tip-top shape. If I buy the same old lead-acid batts.. Looking at this 48v pack. https://bigbattery.com/products/48v-...on-power-pack/ It might be chargeable with the TS-45 if I turn off the PWM and tweak the charge & float voltages. |
48v bdgr - nmc - 80ah - 3.9kwh
After testing the old 48v pack, I found the old 12v Duralast batts might still be pretty good. The cheap HF tester showed 400 to 550 Cold Cranking Amps. These are rated at 800 CCA new. So, I plan to keep them for a while longer, in case the new 48v pack fails.
This 48v pack is a new release "Generation 2" that's packing 80 Ah. "KIT 48V BDGR - NMC - 80AH - 3.9KWH" https://bigbattery.com/products/48v-bdgr-kit-of-2/ Should be here tomorrow. I hope to get it installed and tested this weekend. Tonight I removed the LA batteries without any back injury.. The old Solar controller is now programmed to charge at 50.4 volts. I have a new 2000W SineWave inverter to replace the old 2500W MSW unit. Here's a video: https://youtu.be/bNh9g0tZIns I will keep the old one for a back-up incase the new Sinewave unit fails. The old Morningstar - Tristar 45A Solar charge controller has been working so well, I'm buying a spare with my free money check. https://www.amazon.com/gp/product/B0012DNFT2 Anyways, I hope to run part of my home on the back-up system on the weekends. When I'm home all day and leave my PC on much of 48 hours. It will also be running my Wifi router and the FiOs box in basement and the small freezer down there. During sunny summer weekends, three 200w panels will be bringing in up to 600W. So, I'll want to be using more than that, to cycle the new 48v pack.. Maybe the new inverter will be able to run the Santa Fe dehumidifier.?. It runs at about 600 watts, but I think the start-up is going to be pretty high. I could run it with the blower fan ON all the time. So it's start-up wouldn't be added in with the compressor start load. |
120 Ah 50.4v
The rains have started. The sun is only been out a couple of days this past week.
Flooding season is here. But, I've got 5.85 kWh of NMC Li-Ion fully charged. Untested, because we didn't have time. :( |
Using my 48v backup to run light loads
Trying to see if the backup system can cut grid power use.
Started last month and it looks like about 1 KWH per day was used to power the basement freezer and Fios loads. The AC meter on the inverter output shows 30.358 KWH for Nov 22. The solar controller shows 34 KWH. 30 x 30 cents per KWH is about $9 USDs. Solar wasn't very good for the month.. https://pauland.net/monthradiation.webp |
About half the days this month were overcast! :(
The 800 watt array is working everyday sunny day now.
I ordered a Yolink SpeakerHub. I can trigger a Yolink Routine when the Yolink temperature Sensor hits an alarm limit! I set the limit for 90F and put it in a south facing window. When the sun gets bright, it gets up to 90F and triggers a Yolink routine. The Yolink speaker says (custom) "Hey Google, turn on the Inverter". My Google Hub, controls all the Meross Outlet 120Vac switches. The switch named "Inverter" turns on, drives a relay that activates my 3000W Sine Wave inverter. The Alert Interval is set for 60 mins. (if the sun is still warm, we get a new Alert every hour). My Merross AC switch is set to run max run time of 65 mins. If it gets a restart every 60 mins, it keeps the inverter running until the sun is about to go down. My inverter is driven by a 48vdc battery bank, but when it's charged, I can use the 800w solar panels to run some of the loads in the basement. Freezer, Fios system, inhouse ethernet gear and a PlaneFinder tracking system. (ADS-B receiver connected to the web). The main loads are the sump pumps. When the basement sumps flood! Like we just had when all the snow melted. The loads only add up to about 1 KWH per day now. But when it warms up, I'll be adding on the basement dehumidifier. We might even have more sun in the summer! :) |
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