OffGridInTheCity
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- Dec 15, 2018
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To recap - I have a continued interest in powering my overall home to a livable degree. Last year, the 12.85kw PV array produced 15,000 kwh of useable power. The main problem is *winter*! Nov/Dec/Jan (you can see in previous post) is at 500kwh for the month - just too low to have any chance to 'power the house'. I keep niggling in my mind how to produce 500kwh extra / month for those 3 months so I could have at least 1,000kwh/month to work with.
Producing power is a 'big deal' if you go generator... wood, gasoline, propane, all require a lot of work. And when you think long term (5, 10, 15yrs) its gets daunting. I recently found numbers for Propane in this article - https://preparednessadvice.com/propane-powered-generators-best-choice/ Specifically, this section:
How much propane will my generator burn per hour?
Doing the math I get 4.6kwh / gallon of propane. To do 1,500 kwhs for Nov/Dec/Jan I'd need 326gallons of proane! just for 1 year, not to mention burning up a generator. Agh - it seems like its so much fuel to produce electricity. And the $... a tank is at least $1000, and the fuel is 326gal * $3.00'ish is at least a $1000 and the generator. So $3000 just to think about it and for only 1 year.
SO I'm back to a stock of emergency solar panels to store under the house and to deploy them in the yard if an emergency/winter. I found 40 x 285w 9yr old SunTechs for $73 each. This should produce close to the extra 500kwh/month in winter I'm looking for. I'll let you know how they measure up when I get / test them.
I'm going to test each one against an unused 3yr-old SolarWorld 285w panel to verify they have 80%+ power generation left.
You can look at it either way - 1) its annoying that 'fuel' (like propane)/generator is so costly to create kwh or 2) that panels do such a great job in terms of quiet, no maint, etc.
I think for me, panels are how I'm going to fill that 'itch' in my head for a whole house backup generator
Producing power is a 'big deal' if you go generator... wood, gasoline, propane, all require a lot of work. And when you think long term (5, 10, 15yrs) its gets daunting. I recently found numbers for Propane in this article - https://preparednessadvice.com/propane-powered-generators-best-choice/ Specifically, this section:
How much propane will my generator burn per hour?
- It requires 2 horsepower to produce 1000 watts of energy per hour under load
- Under load each horsepower consumes 10000 BTU per hour
- Propane contains 92,000 BTU per gallon
- Propane weights 4.2 pounds per gallon
- 10 horse power at 50% would use 5 HP to generate 2500 watts of electricity
- 5HP X 10,000 BTU would consume 50,000 BTU per hour
- 500 gallons X 92,000 = 46,000,000 BTU of energy in a full 500 gallon tank
- 46,000,000 BTU divided by 50,000 BTU = 920
- A 500-gallon tank that is full would run a 500-watt generator at ½ capacity for 920 hours.
Doing the math I get 4.6kwh / gallon of propane. To do 1,500 kwhs for Nov/Dec/Jan I'd need 326gallons of proane! just for 1 year, not to mention burning up a generator. Agh - it seems like its so much fuel to produce electricity. And the $... a tank is at least $1000, and the fuel is 326gal * $3.00'ish is at least a $1000 and the generator. So $3000 just to think about it and for only 1 year.
SO I'm back to a stock of emergency solar panels to store under the house and to deploy them in the yard if an emergency/winter. I found 40 x 285w 9yr old SunTechs for $73 each. This should produce close to the extra 500kwh/month in winter I'm looking for. I'll let you know how they measure up when I get / test them.
I'm going to test each one against an unused 3yr-old SolarWorld 285w panel to verify they have 80%+ power generation left.
You can look at it either way - 1) its annoying that 'fuel' (like propane)/generator is so costly to create kwh or 2) that panels do such a great job in terms of quiet, no maint, etc.
I think for me, panels are how I'm going to fill that 'itch' in my head for a whole house backup generator
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