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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> How much power does the average household require? https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1515628926 Message started by TuftyDave on Jan 11^th, 2018, 12:02am

Title: How much power does the average household require?
Post by TuftyDave on Jan 11^th, 2018, 12:02am

OK, I know the kW 'power' versus kWh 'Measure of amount used'
So I'm looking at a tiny pico-hydro generator that generates up to around 1kW of power. I only want it to charge batteries, but
I then read 'this is enough to power an average house'!!!!
I have a kettle that is 2kW and a 3kW electric fire, if they're both turned on that's a demand of 5kW right there. How can a 1kW generator meet that demand???
So I look at online graph supposedly showing the load in an average house over 24 hours. It reckons peak load is around 7pm when loads of devices & cooking are all on, but it shows the demand as only around 700 watts????? Not even 1kW????
Can someone explain please, this is driving me mad!

Title: Re: How much power does the average household require?
Post by Lectrician on Jan 11^th, 2018, 5:28pm

Peak demand is just that. If two appliances draw 5Kw, they need a generator to deliver 5Kw. That's it. Simple!

The graph you are looking at is probably looking at how many Watt-Hours are used in an hour, and then averaging this out over that time.

A kettle and shower are short duration peaks. The generator would still need to be able to deliver the full demand for these peaks.

Renewable firms often mislead with their graphs, charts and figures.

Title: Re: How much power does the average household require?
Post by CWatters on Jan 11^th, 2018, 10:54pm

+1

Peak demand is much higher than average demand.

Work out how many units (kWH) of electricity you use in a year from your bills. This info can also usually be found in your online account. Then divide that by 8760 (number of hours in a year) and you get the average power consumption in kW.

Example: I know someone who uses 10,000KWH a year so their average would be 10,000/8760 = 1.14kW but most peoples average is lower than that.

Title: Re: How much power does the average household require?
Post by Natedog on Jan 13^th, 2018, 3:24pm

Your kettle draws a fair bit of power while it's on, but it only takes 2 minutes to boil and then it's switched off again for hours