15KW O'Clock

randombar

Hi folks,

So getting there with new PV / HP / EV set up.

Currently with energia 2 - 6 rate.

20kwh of batteries charge up in 2 hrs (2 inverters) (10kw)

Hot water takes 2.5 hours to heat up with heat pump (15 deg to 50 deg) (5 to 6kw)

After that house heats up (5 to 6kw)

Only after batteries charge realistically can I charge the old leaf (3kw)

So can really only get 6kw onto the car during the cheap rate OR (thinking out loud) I could maybe prioritize the car charger get 12kw on and send 7kw to the batteries for 3 hrs.

I guess what I'm wondering is, there's really no way of getting a second EV and charging that on the cheap rate too?

Realistically I have 60kwh to use each day on the cheap rate.

Would welcome people's thoughts.

listermint

Wouldn't increasing solar but the obvious answer, then you could dedicate the cheap rate to the car. Which you need during daytime hours. And the solar to the house operation or daytime charge of the batteries.

JayBee66

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.

Jonathan

https://www.boards.ie/discussion/2058330567/15kw-oclock

Stump up the €2k and upgrade to a 16kVA supply?

graememk

What do you need on a day to day distances you need on the car?

Does the charge point you have load balance?

Whats your MIC again?

Your DHW tank possibly wont ever be down at 15 C, Some of it might be but not all off it.

randombar

https://www.boards.ie/discussion/comment/121594678#Comment_121594678

Both cars day to day don't need much, weekday maybe 6kwh each. (Currently only have the leaf but was considering the change of the other)

Charge point load balances all right.

The MIC is 16KVA, maybe I can push to 16kw but don't want to blow anything going over that.

Tank temps: https://capture.dropbox.com/YTrYHDYSSJe3PLgd

Final solar install will be: 13.7 currently 10.3 but getting nothing these days (2.5 today, 3.3 yesterday)

graememk

https://www.boards.ie/discussion/comment/121594841#Comment_121594841

16kW is at 220-230V is 72-69 amps. Well under the consumer 80A and the 100 ESBN fuse.

5kW for the batteries

5kW for Heatpump, DHW (really? what size is it? mine only pulls 3.8 flat out, Usually more like 3-3.5).. How big is the DHW tank?

Whatever the house needs

Car gets whatever is left over. for the 4 hrs.

randombar

https://www.boards.ie/discussion/comment/121594916#Comment_121594916

Might see can I make a few changes to my consumer unit so to allow for 80A fuse.

Every little bit helps.

DHW is 300Ltrs

12kW Mitsubishi Split heat pump

Need to put a proper monitor on it to see what it's actually drawing.

DC999

https://www.boards.ie/discussion/comment/121599738#Comment_121599738

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

ELM327

I have 12kva and generally draw 15kW for 8 hours most nights in the winter. With a 16kva connection you likely have an 80A consumer fuse and a 100A networks fuse. You should be able to draw 18-19kW without issue. 80A at 230V is 18.4kW for instance. So even if you have a relatively low voltage 18kW is fine.

S'

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.

slave1

https://www.boards.ie/discussion/comment/121600561#Comment_121600561

What grid setting do you have your Zappi set at, try 63a to max 12kVa supply. But your drop from 7kW to 1.4kW is strange, if it was a grid limit it would only drop a little bit

S'

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.

slave1

perhaps try another EV if possible to narrow it down, does not sound like a grid problem (but you never know)

graememk

https://www.boards.ie/discussion/comment/121601144#Comment_121601144

CT wired directly into the Zappi or via eddi or harvi? Possibly a loss in signal?

S'

https://www.boards.ie/discussion/comment/121601965#Comment_121601965

CT wired into Harvi, I check the charge again tonight & graph the readings in HA

bullit_dodger

https://www.boards.ie/discussion/comment/121600345#Comment_121600345

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

Surely not?!

graememk

https://www.boards.ie/discussion/comment/121603203#Comment_121603203

Its not every night, car was sub 10%, and that was a 80% charge...

bullit_dodger

https://www.boards.ie/discussion/comment/121603291#Comment_121603291

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

graememk

https://www.boards.ie/discussion/comment/121603437#Comment_121603437

Mrs normally has. 80km.commute uses about 20kWh, thankfully mines 50m

If both of us had that commute thats 40/day.

ELM327

https://www.boards.ie/discussion/comment/121603437#Comment_121603437

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.

slave1

https://www.boards.ie/discussion/comment/121603203#Comment_121603203

It's where we're headed, multi EV households, batteries and HP

randombar

https://www.boards.ie/discussion/comment/121600345#Comment_121600345

Checked the CB in the meter box, it's actually only 63A

https://capture.dropbox.com/Xc8RiZwB83R6Jukb

Recently upgraded to a smart meter so maybe he put that in but I'm guessing that should be 80?

ELM327

Is that the consumer unit or in the actual meter box? The networks fuses are bigger than that and generally before the meter AFAIK.

In either case, you've paid for a higher MIC and you can't use it with a 63A fuse. If it's in your consumer unit you'd need an electrician to swap out the fuse and do associated potential wiring, but if its in the networks side of things then they have your MIC wrong. 63A is 12kva not 16kva

ELM327

https://www.boards.ie/discussion/comment/121605637#Comment_121605637

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!

randombar

https://www.boards.ie/discussion/comment/121606827#Comment_121606827

That's in the meter box.

Also has this: https://capture.dropbox.com/R99ab4uPAPfJMSQ9

graememk

You sure you have a 16kva supply?

Smart meter install wouldn't have changed the consumer mcb

slave1

https://www.boards.ie/discussion/comment/121606838#Comment_121606838

I'm in same boat on HP (doubt I'd get grand) but I have well insulated house, without a well insulated house a HP will cost a fortune. Bucket of coal does me for 24hrs of warm house. If I was "out the country" I would not bother with HP and just insulate the crap out of the house then bulk buy coal from the N, a 10MT delivery should last 12+yrs

S'

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.

randombar

https://www.boards.ie/discussion/comment/121607179#Comment_121607179

Emailed the networks crowd and they confirmed a 16kva supply a while ago.

I didn't think the install would have changed the CB either but it looks very new and I don't think anyone else can change it?

DC999

https://www.boards.ie/discussion/comment/121607226#Comment_121607226

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.