diy solar

diy solar

Free Power is AWESOME!!!

I use 10-12 kWh/day in winter in a much bigger house. I'm home on the computer all day, but have gas heat and hot water.

Yeah, I am pretty sure my tenant uses electric space heaters. Tenant pays tenant's own propane, but I pay the electric bill as there's no official meter (only my sub meter). In summer this tenant uses 7 to 10kWh a day. 2 people, lots of electronic gadgets like surveillance cameras, computers etc.
He multiplied 10kWh per day with the number of days in 3 years. The mistake is that on average across a year, it's probably 30kWh a day.

That is why I asked. At 10kWh per day, I can't see how it can pay for it's self in 3 years. Even at $.25 per kWh that is only $912 per year. $20K - 30% tax credit = $14K = 15 years ROI. Something does not compute. Even at 30kWh per day, it's still 5 years. (@ $.25kWh).
I guess I wasn't clear on what I did, so I'll try to clear up some of the confusion. I am using about 10Kwh of battery daily but you can see it has been rising as the month of Feb goes on. My pay back calculations are based on my average power usage over the past 3 years 30,000Kwh - 33,000Kwh for the year during my previous electric contract. I was paying $0.066/Kwh and about $0.033/Kwh for delivery charge. The going rate in my area seems to be about $0.155/Kwh Plus delivery charge of about $0.055/Kwh now. That works out to just under $7K for the year if I had not installed my system. The first month on our new plan with my batteries installed (and yes I have the required grounding. You can't see it but it is there) We did not use any electricity from the grid during the time of day the electric company charges for power. We charged our batteries during the night and ran from battery during the day for free. It appears our daily usage has risen to 10Kwh to 14Kwh per day time. We have done some things to minimize our usage (installed LED bulbs several years ago), installed soft start devices on both of our AC units (although we have only used one of our AC units so far this year) we also do things like laundry in the evening and we run our pool pump at night. Our power company charges a base fee that works out to about $14/month (although for some reason our first month we were charged $12.97). When we signed up with them, they offered a promotion giving us a $15 gift card into our Amazon Prime account every month for the duration of our 2 year contract. So we actually made $2.03 on the first month. In June July and August I expect to use more power daily than my battery capacity, so I have decided to purchase solar panels. I think adding solar panels actually makes my system less profitable because the cost of the power I may have to purchase will be way less than the cost of the panels. However, the main reason I plan to install panels is because I want to have a backup source of energy. If the grid goes down, I should have enough power from the panels to charge my batteries at least partially. If we conserve, we should be able to keep the frig running and run the furnace fan (we burn gas for heat).
And finally, we should be able to take advantage of the 30% tax break from the IRS to bring the cost down to about $14,000. If you divide $14,000 by $7K it works out to about 2 years for pay back. I keep saying 3 years in case we have to pay for energy in the summer or if we have a breakdown and have to buy energy while we make repairs. Honestly, I wasn't trying to say I have invented electricity. I'm just saying I have found a way to use batteries and an inverter to get electricity (when amortized over 3 years) at no cost or VERY low cost! If that makes some of you uncomfortable... oh well!
Yes I am monitoring the battery temps daily and expect to need to add fans for the summer or remove the insulated plywood panels completely during the summer months.
I had another idea that is kind of a modification of something I saw on a Youtube video. Some guy used an old freezer to keep his batteries warm in the winter by installing the battery and a light bulb in the freezer box. My thought is to purchase a medical freezer (Accucold) they used to transport the Covid vaccines around in vehicles and use it as a cold source. I think it might work to cut a hole in the side of the freezer chest and plumb it with a 4in duct into my battery cabinet (near the bottom at one end). Then install a "muffin" fan near the top of the cabinet at the other end to pull air through the cabinet and out. That should draw in cold air from the freezer and lower the temp...
Good plan.

I expect to need to make modifications to my fans too by June.

Would be nice to automate this, without a full fledged AC.
I was able to buy a thermostat controlled outlet plug made by Inkbird. I turns on my heating pad inside the cabinet to keep my batteries warm and it has a cooling connection that I plan to use for the cooling control. The thermostat turns power on to the correct outlet based on the temp control settings. Heating has been great so I think it will work for my freezer idea to cool my batteries.