15KW O'Clock

Real world questions need real world answers...

Have you tried towing a second EV in neutral with the Leaf and putting some regen into the second EV? When the battery's empty on the Leaf you jump out, into the second EV and tow the leaf.

And when monitoring it, for a few nights you could change the time stuff runs. Then you can track device by device. Ok, you won't run those in the cheap window during that 'test'. So start device X at 2am and let it finish with nothing else running. Then you know the usage and time it ends. Rinse and repeat

I'm on a 12kVA connection and having some issues with car charging. Zappi would charge at 7kW (32a) for 20-30sec and then go back to 1.4kW (6a), this would keep repeating over the 3hr window (Pinergy)

I wonder is this due to low grid voltage? I was drawing 15kW from the grid at the time.

Ya, I’ve checked the grid limit and it is set to 63a. Strange thing is, it charged at the full 7.2 kW the previous day within the 3hrs. I did a software update lastnight on the Model Y so thought it might be that. Did a soft reset (holding down two buttons) but no luck.

"15Kw for 8 hrs most nights". For reals? That's like 120Kwh every night, or 3500+ a month?

Surely not?!

The question was more for ELM327 - it seemed like.... a lot! :-) Maybe with a EV and doing big mileage though it's needed? Dunno.

It's not for 8 hours every night. But it is for example at the weekend where we often have 2 200+km days, as well as topping up the house batteries etc. 3 evs, home storage, running other stuff at night too, it all adds up!

Other nights the 15kW may drop after 1-3 hours depending on what needs charging. But in the winter, theres at least 1 EV charging every night as well as the house battery.

Yup. It's how the grid can be equalised too. More and more people charging at off peak times. We have 3 evs and large storage, but no heat pump yet. It's been on my list for years at this stage. We don't qualify for the grant so it is quite expensive up front, but everytime I pay 1k for oil I lament that that 1k could have gone towards the heat pump!

Only checked mine recently and found out that I had an 80a in the consumer unit.

Rang ESB and they confirmed I had a 12kVa connection😳 Makes no sense.

But heat is heat. If coal heats the house, so will a HP.

So unless other heat sources cost a lot, then a HP won't cost a lot to run. Unless people change the temp they want. Or it's a bad design and install.

Heat is heat, stored energy is stored energy, and energy efficiency vs cost is the consideration. If it takes X kwh equivalent of coal at 2c per kwh and x/5 kwh of electricity at 13c per kwh for instance then the coal is cheaper. We only use the coal and log fire for heating topup or for ambience in the winter, as well as novelty tea/milk/hot chocolate/espressos.

I'm looking at a HP for cost savings and the removal of hassle of "oh is the oil running out, great thats another grand" etc. Whether you have a F or A1 BER , you can use coal, oil, HP, or anything else to generate heat. The ultimate questions for me are cost and convenience. We have a B2 BER, so not bad. Not bad enough in fact, that we don't qualify for the windows grant (which i want to do, we only have double glazed) or the heat pump grant, as you need below B2 for those.

I already have the walls pumped and the attic well insulated. The whole house is block built so the insulation is pretty good even without those. The main heat loss is the windows and the vents.

This is my setup. Not sure why the electrician put in an 80a MCB.

So if it's 80a ESB side can I draw more that 15kW at night?

That's not an mcb, it's an isolator. Do you have an mcb in the meter cabinet? That enclosure next to the smart meter probably has a 63a mcb in it.

The main switch in the consumer unit is just an isolator that's capable of breaking 80 amps. Its sole purpose is to switch off the power to the board for maintenance. Nothing more than a heavy duty switch.

The 63 amp mcb in the meter cabinet is your main house overcurrent/short circuit protection, which must be less than the Esbn 80 amp to make sure it trips before blowing the 80 amp fuse.

The ESBn fuses (and fuses in general) don't blow straight away all the time. I've drawn over 63A at times (as, I have 80A coming in to the house split into 63A and 40A twin main boards) by mistake as I forgot to load balance. It may trip after a few seconds, or minutes etc.

I wouldnt recommend tripping the ESBn fuses as they like to charge callouts for that