Tesla Power Wall ....

[Octopus]

I was in Cambridge yesterday and Tesla had a unit in the main precinct where they had a couple of their cars and the Power Wall unit ......

Anyone got any experience with this technology?

To me it seems a fairly good idea, to charge a battery and use it "later"

Any views?

 

[ruston]

Don't know much about them , but had a quick look.
My first reaction is - poor grid.
Home Charging Installation - https://www.tesla.com/en_GB/support/home-charging-installation

 

[telectrix]

it'sOK the car will catch fire and burn up before the charging installation fails.

 

[LeeH]

When I looked at them I couldn’t get the numbers to add up.

I do like the idea and hope to have one at some point.

 

[Gavin John Hyde]

not too sure about the power wall, although they recently built a giant battery storage system in australia to harness solar power, they told the government if its late its free, they had it done ahead of schedule and works brilliantly apparently.

 

[telectrix]

not too sure about the power wall, although they recently built a giant battery storage system in australia to harness solar power, they told the government if its late its free, they had it done ahead of schedule and works brilliantly apparently.

yeah, but that's in Oz. they have sunshine down there when we have rain. we need to invent a system that generates electrickery from rain, fog and sleet. now that would be a winner.

 

[whinmoor]

In my opinion the Tesla Powerwall 2 is really too big for a typical UK system. The capacity is 13.5 kWh. You need to be generating 20 kWh from PV to fill it after deducting some for covering baseload.

I reckon a typical 4kW PV system manages 20 kWh on less than 50 days a year. It manages less than 5 kWh on more than 100 days a year so on those days the battery would receive no (or very little) juice.

So, according to my analysis, on 100 days the battery would be virtually empty. On 50 days it would be totally full. And on around 215 the battery would be partly full.

 

[telectrix]

And on around 215 the battery would be partly full.

similar to my beer jug, then.

 

[LeeH]

I wonder what the likely hood is of them lasting past their warranty.

 

[saint]

To make battery storage cost effective we should be concentrating on reducing or removing the base load of the building which accounts for 50-70% of the total bill. Trying to power the electric shower or induction hob like the Powerwall 2 seems to be trying to do doesn't add up to me.

 

[whinmoor]

Surely the aim is to charge their cars...as quickly as possible. That's why the Powerwall has a fast discharge rate. There's not much point in having a Powerwall without an EV for most households.

 

[infinity]

We have installed a lot of Powerwall 1's and 2's. They do seem to work very well. We have customers now only importing less than 0.4KWh most days.
Most customer do not have EV's, but they are at work all day when the solar is being generated. This way when they get home all their solar has been saved and ready to use through the evening. If you size the system correctly and install the battery with a Pv system them the numbers do stack up do the fact you will only pay 5% VAT on the battery as opposed to the 20% on a retrofit.

 

[LeeH]

So what is the retrofit cost? And can you breakdown the payback time?

 

[mrbroons]

The other aspect with PW2 (the latest one) is that it can timeshift normal grid power. So in deepest winter you can charge up on very cheap grid power in the dead of night (see Octopus Agile Tariff or similar) and then use the cheap power when needed. So even in the Winter or without a solar system at all a battery (but specifically PW2) will effectively save you money. Don't get me wrong the payoff time is still horrific but not as bad as you would have at first thought with time-shifting now available.