Tesla - Solar roof panels on pre-order

OmegaRed

So Musk has finally set his "Grand Unification Plan Into Motion". Solar panels to run your house and charge your car. Truly off grid and zero emissions living. I find this all very existing
Just to be clear, I live in Ireland and don't own a house. I do understand there is a cost to purchase this equipment but still, this stuff is a game changer when it comes to climate change and how we use electricity.

I know this is probably asked here a lot “would solar power work in Ireland”, but with a system like that from Tesla and their Powerwall units, do you think it would be possible to run your entire home using Tesla products?

KCross

Possible, but not financially practical yet.

The Model S is €85k!
The Powerwall is about €6k, I believe, and if you wanted to go off grid you'd need more than one.
I don't know how much a Solar roof is, but Im sure all-in its not cheap.

Maybe when the Model 3 comes in (~€40k) and the other products drop in price and there are more government incentives and a grid Feed In Tariff it might work then.

unkel

KCross wrote: »

The Powerwall is about €6k, I believe, and if you wanted to go off grid you'd need more than one.

Going off grid with it in Ireland using solar is not a viable option. Not even if you had 100% of your south facing roof of your semi-d plastered with PV panels and if you had 10 Powerwall 2 installed.

The good thing is that you only need 1 Powerwall typically in Ireland. It has 14kWh storage. If you fully use that every 24h, you will have used 5,000kWh per year. The average Irish household uses 3,500kWh per year

With or without solar, if the Powerwall 2 is not fully charged by sunset, you could charge it up with cheap night rate electricity so you have a full battery first thing in the morning

quentingargan

unkel wrote: »

if the Powerwall 2 is not fully charged by sunset, you could charge it up with cheap night rate electricity so you have a full battery first thing in the morning

.... and then have nowhere for your solar electricity to go next morning. You need a more nuanced night-charging that leaves enough room for the batteries to be charged by solar during the day. And you can never get that totally right.

For this reason, 100% cycling of your battery is never going to happen, so the payback gets kicked back another decade or two.

antoinolachtnai

Electricity isn't really that much cheaper at night. If there is a glut of solar on the grid, then daytime costs will fall considerably. The glut doesn't necessarily have to happen in Ireland. Extra solar in U.K. and on the continent will also have an impact.

unkel

quentingargan wrote: »

.... and then have nowhere for your solar electricity to go next morning. You need a more nuanced night-charging that leaves enough room for the batteries to be charged by solar during the day. And you can never get that totally right.

Indeed. I'll admit I was actually thinking of the possibility of using the Powerwall without any solar

If you can "move" 3500kWh per year from day time use to night time use with the Powerwall, the payback time is about 20 years

Might not be an outrageous solution for a large family / large house or even a business with lots of day time use of electricity

KCross

unkel wrote: »

Indeed. I'll admit I was actually thinking of the possibility of using the Powerwall without any solar

If you can "move" 3500kWh per year from day time use to night time use with the Powerwall, the payback time is about 20 years

Might not be an outrageous solution for a large family / large house or even a business with lots of day time use of electricity

What would the state of the batteries be though in 20yrs? I know they provide a decent warranty but its probably like the EV's... which is that they guarantee something like a min of 70% and will up it to 80% and thats it. Its not like it will be at 100% in 20years time and your replacement costs might eat away at the savings.... but worth looking into nonetheless.

20 years is also a very long time to tie yourself into a payback particularly at this early stage of Powerwall tech.