I'm driving on sunshine (whooah)!

eagerv

https://www.boards.ie/discussion/comment/120724245#Comment_120724245

I think that if you want to be paid for the actual amount that you export, then yes.

We have a day/night meter and we get an estimated amount of credit each bill. Not much, but then again we export almost zero..😉

micks_address

https://www.boards.ie/discussion/comment/120724300#Comment_120724300

How does deemed export work? How is the estimate come up with?

eagerv

https://www.boards.ie/discussion/comment/120724320#Comment_120724320

Not sure, but I think our electricity supplier was contacted by our solar supplier when grant was being sorted.

Mr Q

https://www.boards.ie/discussion/comment/120724320#Comment_120724320

There is a formula for it based on your inverter size. I think it works out about 300kWh per kW of inverter. Someone else here will probably have the formula.

the_amazing_raisin

https://www.boards.ie/discussion/comment/120724320#Comment_120724320

Here's an example of the calculation

EDIT: better link

https://www.bordgaisenergy.ie/home/help/what-is-deemed-export-quantity

the_amazing_raisin

Stats for June, vast improvement without the commute. Mostly just driving around Dublin with a week of not moving because I was on holiday

Solar charging: 118.35kWh

Grid charging: 1.38kWh

Solar percentage: 98.85%

Charging cost at 14.53c/kWh: €0.20

Average electricity price (cost/grid+solar): 0.17c/kWh

Distance travelled: 640km

Average speed: 29km/h

Indicated consumption: 16.5kWh/100km

Actual consumption (incl losses): 18.7/100km

Distance travelled on solar only: 632km

Average cost per km: 0.03c/km, might as well round it to 0 😁

unkel

My stats for June (largely making it up 😂 but both cars driven entirely on solar PV)

Solar charging 400kWh

Grid charging 0kWh

Public charging 0kWh

Average cost per km: 0.00c/km

the_amazing_raisin

https://www.boards.ie/discussion/comment/120791299#Comment_120791299

When your Zappi starts, does it start from the full 7kW and then drop down to stay within the surplus solar?

Mine does that, and the 1.38kWh from the grid is entirely from that alone

Black_Knight

https://www.boards.ie/discussion/comment/120791367#Comment_120791367

Ditto. Though I'm less than 98% or that. This last 2 months I've pulled in 41kWh during the day (nevermind night), and for the life of me I can't fathom how. Pretty much solar covering us every day in that period.

unkel

https://www.boards.ie/discussion/comment/120791367#Comment_120791367

Zappi is out of action the last week or two, so just grannying it and charging on my neighbour's zappi. New zappi V2 on the way! But yeah I typically buy a fraction of a kWh from the grid per day because of swings in PV production and timing issues and not entirely accurate CT readings.

slave1

Got 545kWh into the EVs in June, around 3,300kms after losses

the_amazing_raisin

https://www.boards.ie/discussion/comment/120791504#Comment_120791504

Is it when your usage is going over your max inverter output?

Also do the Zappi, inverter and meter agree? I'm always a bit suspicious about the CT clamp's accuracy, I seem to end up with a fair number of glitches

I go off the meter for measuring import since that's what I pay for in the end

the_amazing_raisin

https://www.boards.ie/discussion/comment/120791513#Comment_120791513

Yeah I suspect that the majority of the import is down to CT inaccuracy. Not sure if it's even real but in the interest of honesty I'm going to report exactly what the Zappi reports

I'm slightly annoyed because I was slightly off 99% green driving, I'll just have to content myself with 98% 😁

axe2grind

Charging from the Zappi, I managed 282kwh out of 320kwh from solar. Unfortunately about half of the non solar was with day rates as I had to do a 3 hr charge after being away overnight before heading off on another long journey.

the_amazing_raisin

Stats for July, absolutely rubbish weather combined with a few long trips means I only managed slightly more than half my driving on solar

-Solar charging: 128.45Wh

-Grid charging: 90.86kWh

-Solar percentage: 59.57%

-Charging cost at 14.53c/kWh: €13.21

-Average electricity price (cost/grid+solar): 6.02c/kWh

-Distance travelled: 994km

Average speed: 32km/h

-Indicated consumption: 17.3kWh/100km

-Actual consumption (incl losses): 22.1kWh/100km

-Distance travelled on solar only: 582km

-Average cost per km: 1.33c/km

Still pretty good going, but I don't see August being any better so far

eagerv

https://www.boards.ie/discussion/comment/120943759#Comment_120943759

The last month has been poor alright, have seen better solar days in winter.

Don't have figures like yourself, except just got my last two months bill. Only 72kWh at expensive day rate (29c). Remainder 620kWh at night rate (8c). That's with two cars charging at night, less some free by day. Cannot complain..

DaveyDave

Last month wasn't too bad, a 13% drop from the previous month generation for me. Not what you'd want for July but not terrible considering the weather we got.

@the_amazing_raisin what capacity PV do you have?

the_amazing_raisin

https://www.boards.ie/discussion/comment/120943848#Comment_120943848

Yeah I was down 16.5% on June for generation

There's still enough to keep the house going, including powering a mega bouncy castle for a weekend. So the bill is still not much, and what consumption there is is mostly night rate

I've a 6kWp South facing array with a 10kWh battery

The main issue is that there isn't enough left over for the cars. Mostly my wife charges for free in work so she's sorted, just need to magic some extra electricity for my car

Black_Knight

May:

536kWh generated with 91% utilisation, giving 485kWh of solar used.

182.94kWh of that green energy went into the car. 188.58kWh total into the car. 97% green driving which averages to 0.4c/kWh to charge the car this month.

Actually had too much solar this month, and had to export energy as every battery was full.

June:

528kWh generated with 82% utilisation, giving 435kWh of solar used.

131.78kWh of that green energy went into the car. 176.21kWh total into the car. 75% green driving which averages to 3.8c/kWh to charge the car this month.

July:

450kWh generated with 83% utilisation, giving 373kWh of solar used.

119.09kWh of that green energy went into the car. 244.83kWh total into the car. 48% green driving which averages to 7.7c/kWh to charge the car this month.

No idea how far I drove. VWsFriend stats will have that when i'm back home.

Fian

Just out of curiousity - is there a reason BEVs don't seem to come with a solar roof constantly feeding the battery when in sunlight? Is it because of the risk of it being damaged, that it just wouldn't make much difference or because they are keen to include a panoramic glass roof? Just strikes me as odd that nobody is building a PV into the roof of cars so I imagine there must be a straightforward reason for it and a car roof seems to be big enough for a decent size PV panel. I guess it would be an easy vandalism target when car was parked, maybe that's it?

allinthehead

https://www.boards.ie/discussion/comment/120953379#Comment_120953379

It's no easy task to integrate into the roof of a car and it's expensive to do. Gains are questionable for the effort, having said that the Fiskar Ocean has one and they claim it adds about 1500 miles a year in a sunny climate.

DaveyDave

I believe the American Prius has one, or had one at some point but it's used for cabin cooling I think. The gains are marginal for the cost to implement them. I think someone worked out that at $1,000 or whatever it cost it would take like 23 years to pay back. Of course paying back isn't really necessary if it could function, i.e run AC once a day to reduce moisture etc.

slave1

The original Leaf had a tiny solar panel to "charge" the 12v battery, just a gimmick

the_amazing_raisin

https://www.boards.ie/discussion/comment/120953379#Comment_120953379

It's been tried but the inconvenient truth is you need a lot more roof space than a car has to get any decent amount of power into the car

For example my 15 rooftop panels have so far generated 17kWh which is pretty good, around 100km range in this weather

Problem is that's probably 4 times the roof area of my car. So my car would generate 4.25kWh or 25km range

Might be enough to cover the daily driving, but considering the added cost it's debatable how much it's worth

It definitely wouldn't be worthwhile in my case because my cars are parked on the north side of my house so are almost always in shade

unkel

2 EV household, 100% driven on sunshine for coming up to 3 months now. Hope to get another month out of it!

creedp

https://www.boards.ie/discussion/comment/120943913#Comment_120943913

I get that once you get an EV and especially when you have solar the Holy grail is free motoring but in reality unless you have a massive solar system backed up by wind generation it's inevitable that some charging will be from grid.

My solar generated 20kwh today but I consumed 40kwh of electricity. Now I could claim that I drove entirely on solar or that my house was run entirely on solar but no way could I achieve both.

EV drivers have short memories and have forgotten what it was like to fund their ICE driving. With solar and night rate running an EV is essentially a pittance compared to the cost of most other aspects of one's lifestyle.

unkel

https://www.boards.ie/discussion/comment/120958756#Comment_120958756

Indeed. In my case let me be clear, I have driven 100% on PV for about 3 months now on both my cars, during which time also 100% of my house was powered by PV and 100% of my hot water was provided by solar PV and solar thermal.

creedp

https://www.boards.ie/discussion/comment/120959388#Comment_120959388

Not doubting you but all I'm saying is that for many incl myself this is not feasible. Personally don't have a problem with that as even without solar my EV cost a pittance to run from the grid compared to an ICE, and it cost even less now with solar. All good

the_amazing_raisin

Much better performance yesterday 😁

Black_Knight

https://www.boards.ie/discussion/comment/120953710#Comment_120953710

If cars can trickle charge from such low power. Some cars require less, but most need 1.4kW to start charging. No idea why that threshold must be met, but ain't no solar panel going to produce that for you.