3 ms·

Curious, what is the need for a 5kW array? Do they typically only produce at 5-10% of peak? Or do the relatively low panel prices mean that if you are going to

by ac29 9y ago

Curious, what is the need for a 5kW array? Do they typically only produce at 5-10% of peak? Or do the relatively low panel prices mean that if you are going to build 1kW, you might as well build 5? I just went outside and checked my utility company smart meter... the whole house isnt even using 100W right now (though thats on the low side, I'd think).

kurthr 9y ago
That will change as soon as your fridge/washer-drier/TV much less hairdrier, AC, or stove turn on (it's peaky so net neetering really helps). Typical 3 person SFH uses ~1.5kw average or 1000kWh/mo ($110/mo at CA rates). Well installed solar at US lattitudes in a very sunny area generally gives you something like 25-30% of peak as an average (it's not up half the day and averages less than 45deg over the day ignoring clouds).
IkmoIkmo 9y ago
Lighting/laptops/phones take a tiny amount of energy. For example, a phone battery nowadays (e.g. iPhone 6) is about 10 watthours with say 5 hours of screen-on-time. Disregarding it's on doing background stuff all the other hours, it approximately uses just 2 watt on average. But the very first microwave (oven) I looked up on Bestbuy used 1500 watt, and if you've got something cooking for 40 minutes in there you're easily using 1 kWh, or about three months of iPhone use. > Curious, what is the need for a 5kW array? Do they typically only produce at 5-10% of peak? As for peak production, well yes-ish. The average peak solar hours in the US is about 4 per day, Europe is probably at 3, in Texas it's probably 5. That means a 5kW array will produce about 25 kWh a day, or 750 a month in Texas, saving about $85 a month / 1k a year in electricity purchase at 11.5c a kWh. So yeah, on average a panel in the US produces at roughly 15% or so of peak. (±4 peak hours per day).

3 ms·

Curious, what is the need for a 5kW array? Do they typically only produce at 5-10% of peak? Or do the relatively low panel prices mean that if you are going to

by ac29 9y ago

kurthr 9y ago
That will change as soon as your fridge/washer-drier/TV much less hairdrier, AC, or stove turn on (it's peaky so net neetering really helps). Typical 3 person SFH uses ~1.5kw average or 1000kWh/mo ($110/mo at CA rates). Well installed solar at US lattitudes in a very sunny area generally gives you something like 25-30% of peak as an average (it's not up half the day and averages less than 45deg over the day ignoring clouds).
IkmoIkmo 9y ago
Lighting/laptops/phones take a tiny amount of energy. For example, a phone battery nowadays (e.g. iPhone 6) is about 10 watthours with say 5 hours of screen-on-time. Disregarding it's on doing background stuff all the other hours, it approximately uses just 2 watt on average. But the very first microwave (oven) I looked up on Bestbuy used 1500 watt, and if you've got something cooking for 40 minutes in there you're easily using 1 kWh, or about three months of iPhone use. > Curious, what is the need for a 5kW array? Do they typically only produce at 5-10% of peak? As for peak production, well yes-ish. The average peak solar hours in the US is about 4 per day, Europe is probably at 3, in Texas it's probably 5. That means a 5kW array will produce about 25 kWh a day, or 750 a month in Texas, saving about $85 a month / 1k a year in electricity purchase at 11.5c a kWh. So yeah, on average a panel in the US produces at roughly 15% or so of peak. (±4 peak hours per day).