Geek
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Reading just some of this thread has left me bemused. Not by the issue of using EV charge points for motorhomes, but by the misuse of terms.
Firstly, amps and watts area measure of how fast the electricity is flowing, not how much has been transferred. So Kw, Amp and Watt are speed, similar to mph.
To measure quantity, you multiply the speed by the time, so it is expressed in Kilowatt hours (KWH) or amp hours (AH). For example, 50 amps for an hour is 50KWh. Like 50 miles is 50mph for an hour.
Secondly, voltages give different powers. A typical EV charger may do up 22KW (faster ones are more expensive and less suitable) which at 230v is about 95A. But if it were at 12v it would be 1,833A.
You may have a 70A charger for your battery bank, but that's 70A at 12v, which is only 840 watts, or 0.84KW. A 450Ah battery bank will take over four hours to go from 20% to 80% on that charger. Typically, you pay about 65p per KWh so it would cost less than £2.50.
That much energy as LPG would cost about 80p and fill in two minutes.
Firstly, amps and watts area measure of how fast the electricity is flowing, not how much has been transferred. So Kw, Amp and Watt are speed, similar to mph.
To measure quantity, you multiply the speed by the time, so it is expressed in Kilowatt hours (KWH) or amp hours (AH). For example, 50 amps for an hour is 50KWh. Like 50 miles is 50mph for an hour.
Secondly, voltages give different powers. A typical EV charger may do up 22KW (faster ones are more expensive and less suitable) which at 230v is about 95A. But if it were at 12v it would be 1,833A.
You may have a 70A charger for your battery bank, but that's 70A at 12v, which is only 840 watts, or 0.84KW. A 450Ah battery bank will take over four hours to go from 20% to 80% on that charger. Typically, you pay about 65p per KWh so it would cost less than £2.50.
That much energy as LPG would cost about 80p and fill in two minutes.
