I think 100 households per MW in milder climates is very conservative.
Anectdata: I have a ~150 square meter, 50 year old house heated by electricity and heat pump. I live I Norway, and where I live winter temperatures usually don't get lower than -12C. I have 2 EVs that are driven around 50k km a year combined, charged at home every night, simultaneously.
I peak out below 15kW (1h average). That number is deliberate since I get a higher tariff if I go above 15kW. I have some minor smart house installations that most significantly cuts power to my hot water heater if I get close to 15kW, but even without that I would rarely get above 15kW, and never above 20kW.
Average power this January was 4.75kW, December was 4.96kW, August was 2.25kW.
With a household of 4 and doing everything electrical (cooking, heating, hot water but no electric car) we use on average about 9-10 kWh per day. A bit more in the winter, a bit less in summer.
This is a well-insulated, relatively recent house in western Europe. 100kWh seems excessive to me.
1000kwh/month in the winter and 350kwh in the summer. 4 people in central Europe. We use electricity for heating the house, warm water and everything else. We have an air-to-water heat pump.
There's 10 houses on my street, if every house had 2 cars and each drove 50 miles a day at 3 miles per kWh, and the cars are parked 10 hours overnight, that's 3kW per house
As we can all boil a kettle (3kW), or have a shower (10kW), or cook a sunday roast (5kW), and indeed do those at the same time, it's not a problem.
Indeed. If you're going to be heating all those houses with electricity, instead of gas, coal, or wood, then you'll likely need much more than 1kW per home. Especially when winter hits -30C.
> I can't see any way to go much lower than that without freezing in the winter. 2 kWh/day seems crazy low to me.
Apart from insulation energy required for heating changes massively with local climate and scales directly with living space. So directly comparing those numbers without additional information is quite meaningless.
Here in Germany, which seems to have a roughly similar climate, ~120kwh/m2 and year is the average for a detached home. Modern buildings are usually a lot less though, 30-50 kWh/m2year seems standard. With specialised construction ('passive house') and heatpumps 10 kWh/m2year is well feasible.
A kettle uses ~1.5KW, a geyser ~2KW, an oven ~5KW, a stove about ~3KW. These are fairly high estimates I got from some quick googling. If you add these all up, and account for some more appliances (HVAC, fridge/freezer etc.), I think it is safe to estimate that a household less than 20KW at peak, even though it is a fairly high estimate.
So going backwards from there, 1.2MW = 1200KW and 1200KW / 20KW = 60 households at peak usage. Which is a very conservative estimate.
For future reference I will use 1MW = 50 households as a conservative rule of thumb. Maybe 100 households per MW is closer to reality, but that feels fairly lenient to me.
>You need around 1200kwh per month (annualized) heat a medium home.
I can't believe this is true outside e.g. Alaska, Norway, etc. I live in an area with a lot of cooling needs and very moderate need for heating, almost all of both are done with electric, and 1200 kWh per month is a good guess for total average home usage, heating/cooling, lighting, video games, cooking, all the rest.
Ok, but what do you actually use? I have a very small 3-bed house in the UK, and over the last few months we've been averaging 1100-1200kWh of electricity per month(and we heat using gas, although we do have an electric car).
From May 2019 to January 2020 we used 706kWh. I have a fridge but no other appliances that constantly draw power. I don't heat electrically, but I cook using electricity. I run the washing machine about once a week or so and hang-dry the clothes.
I guess I've used a bit more electricity during the last year because I worked from home more, but I doubt it's a factor 10. 100kWh per day would cost more than I pay for rent...
Another data point. Past 12 months we're at 22,000 kwh. Average of 60kwh a day. Older 4 br house with people almost always in it. USA, TN.
I think the main difference for us is that my wife and some of the kids are at home almost all the time and we kept the house warmer for the baby this winter.
Last month I used 1402 kwh in Washington State, which is high for me.
2600 sq ft home kept at 71f, electric heat pump, & heat pump water heater, but I had a few holes in the walls for several days due to repairs during the coldest month of the winter so far which messed up my average using electric heaters to backfill the gap.
Obviously, the holes were covered over when not being worked on but it wasn't as air tight as compared to buttoned up and fully insulated as usual.
My power consumption is usually 30 to ~75% of that depending on weather and activity.
Let's not get ahead of ourselves, 100kWh is not the "low limit" of how much energy you need to get an temperature controlled home in the South for a day.
This is the figure in an environment where electricity costs nothing and there is zero pressure from home design to the actual AC unit to reduce consumption. Let's face it, this attitude isn't going to fly in the future. You could probably cut that figure by a good 10% by installing your choice of solar panels or a bunch of trees, just from less sun hitting the structure.
(Cut it in half if you consider the average American in the South lives in a freakishly large house fit for a queen with entourage and is cooling all of it..)
We don’t use electricity for heating (heating and warm water are powered by community heat), and need 11kWh per day on average, excluding the EV. The EV adds another 5.5kWh per day.
My Silicon Valley house consumed ~450kWh/month (15kWh/day) (before we bought an EV) which is very much on the low side from what I see here. 1100sqft. No A/C. Rarely run the heat. Every single light in the house is an LED. Gas appliances. 2 people, not home during the day.
Anectdata: I have a ~150 square meter, 50 year old house heated by electricity and heat pump. I live I Norway, and where I live winter temperatures usually don't get lower than -12C. I have 2 EVs that are driven around 50k km a year combined, charged at home every night, simultaneously.
I peak out below 15kW (1h average). That number is deliberate since I get a higher tariff if I go above 15kW. I have some minor smart house installations that most significantly cuts power to my hot water heater if I get close to 15kW, but even without that I would rarely get above 15kW, and never above 20kW.
Average power this January was 4.75kW, December was 4.96kW, August was 2.25kW.
(Edited for typo)
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