Tesla Energy Plan

[AliG]

I got an email this morning re the Tesla Energy Plan

 

https://octopus.energy/tesla/tariff/#/new/

 

Basically if you have a Tesla and PV and a Powerwall, you can sign up to this plan and pay 8p/kWh for electricity. They will also pay 8p/kWH for exported electricity.

 

Presumably they use the Powerwall and your PV to load balance the grid allowing them to provide you with lower priced electricity.

 

I had considered a Powerwall before but I don't think it would pay for itself. Under this plan I would probably save around £7-800 a year which would pretty much pay for a Powerwall. It also says that it will work with my 3 phase supply.

 

So I put in all of my details and it said not available in my area, I don't know why but that is disappointing.

 

Maybe this could work for you @Jeremy Harris

 

 

 

 

[Jeremy Harris]

I seem to remember a very similar plan being offered a couple of years ago, might try and find the details, as I think it was posted here.

 

The biggest problem with these plans is the impact they have on battery life, as they rely on being able to cycle your home battery a lot more, in order to provide a bit of local grid reinforcement.  IIRC there were some estimates of the impact of this last time it was discussed, and they didn't look great.

[AliG]

The Powerwall 2 guarantees 70% of its capacity at 10 years so I think this covers this.

 

When I ran the numbers on the Powerwall 1 it didn't make economic sense as it would wear out before it paid for itself.

 

Even now I think I would probably need a Powerwall 3 with longer lifespan and higher capacity to work properly in my circumstances. Presumably the touted "million mile" battery would work well in a Powerwall.

[SteamyTea]

15 minutes ago, AliG said:

pay 8p/kWh for electricity

 

16 minutes ago, AliG said:

save around £7-800 a year

So that will be around 9,375 kWh, or the annual output from a 10 kW_p PV sytem.

 

Or enough to run my house twice.

 

If it is a 5 kWh storage system, and it uses half of that a day for 'balancing', then that will 900 kWh/year, or £73/year.

 

Am I missing something?

[AliG]

The saving is because they’d be letting me buy all my electricity at the cheaper rate and there is no standing charge also.

 

We use an excessive amount of electricity. About 4000kWh for the Tesla plus around 15000 for the house offset by around 3000 of solar PV.

 

The main reason our electricity consumption is high is a pool pump and dehumidifier that run almost 24 hours a day.

I am always trying to optimise it and get it as low as possible, but getting the family to go along with this is difficult. For example I reckon that the dishwasher can be run every day and a half if properly packed but they want to run it every night.  My method would cut a third from it’s electricity consumption. The same goes for washing towels after one use which I reckon accounts for about 25% of our laundry.

 

Yesterday I was checking how much the washer, dryer and dishwasher used though and it wasn’t that much. Then I checked how much the home cinema used and I reckoned that was the second highest user of electricity in the house. Projectors still generally use incandescent bulbs and are very heavy users of electricity. Apparently the EU are going to mandate they change to lasers or LEDs. I reckon the projector alone uses around 1000kWh a year and you can maybe double that including speakers etc. It does cut the heating bills however!

 

Over time I would like to have more PV and less consumption to get closer to neutral but we are well away from that at the moment. Arguably Scotland will eventually be all renewable electricity at least.

[SteamyTea]

2 minutes ago, AliG said:

The saving is because they’d be letting me buy all my electricity at the cheaper rate and there is no standing charge also.

Right, shall trust your figures on that, saves me getting them wrong.

3 minutes ago, AliG said:

I reckon the projector alone uses around 1000kWh a year and you can maybe double that including speakers etc. It does cut the heating bills however!

Not if you are using extra ventilation to cool the place.

 

[AliG]

The heating has never been switched on in the cinema room. It was 24c in there at 6am this morning whilst it was about 4c outside.

 

I got them to install an extract in the mvhr in there so it helps to heat the air coming into the house.

 

When it gets too hot I just wedge the door open into the hall which is the largest room in the house and it heats up in there.

 

The amount of heat generated shows how inefficient the equipment is. I can see every time someone turns on the projector when I look at the output from my Heatmiser.

 

i am trying to figure out if I can put some of the equipment on a wireless switch so it goes off at night and also so people cannot accidentally leave it switched on.

[Jeremy Harris]

The main problem for us is that, because we don't use much grid electricity (around 4,000 to 4,500 kWh/year), any saving from being on a slightly lower tariff is too small to warrant doing much by way of an investment in something to reduce it.  The numbers for battery storage just don't stack up for us at all well, especially not the Tesla Powerwall, with its oddball controls that mean you cannot directly and easily set the thing to charge and discharge when you want it to.  I was very seriously looking at other, cheaper, and more easily controlled, home battery systems, but even then the cost would never have been recovered through life.  I was working on the basis that having a backup power supply, in the event of a power cut, would be worth paying for, but since our local network had a load of cables replaced last year, it seems to be far more reliable.  It used to be that we'd get a power cut in any sort of a blow, but yesterday and last nights storm was the worst we've experienced here, and the power didn't as much as flicker.

[AliG]

I thought the 8p/kWh export payment might be interesting to you although I think you maybe have to lose your FIT payments to get this.

 

 

[Jeremy Harris]

10 minutes ago, AliG said:

I thought the 8p/kWh export payment might be interesting to you although I think you maybe have to lose your FIT payments to get this.

 

 

 

 

That's the snag!  At the moment, around 65% or so of our electricity is at the cheap rate, 8.148p/kWh.  Our total electricity bill for the year is under £600, but we receive about £1,000 a year in FIT and export payments.  Losing the FiT would be have a big impact.

 

We get paid a bit over 5p/kWh for the deemed export (roughly £150/year) and we also get paid another ~£850 as FiT payments.

[SteamyTea]

1 minute ago, Jeremy Harris said:

Losing the FiT would be have a big impact.

Would you loose the FiT payment?

You can change energy supplier without it being effected.

[Jeremy Harris]

1 minute ago, SteamyTea said:

Would you loose the FiT payment?

You can change energy supplier without it being effected.

 

 

I believe you do, as a part of this deal.  That was certainly the case last time this came up.  It depends on how the battery system is connected, I believe.  If it's AC coupled and doesn't take your max export over the agreed figure with the DNO then I think all is OK, but there is the possibility of there being an issue if the battery system either takes you over the agreed export limit, or if the battery system is DC coupled to the PV system.

[Ed Davies]

28 minutes ago, AliG said:

I reckon the projector alone uses around 1000kWh a year

 

More than 2/3rds of my annual electricity consumption. (OK, I drive a diesel van and heat with oil including DHW but the shower is electric ? )

 

Meter reading 2019-01-30: 40352, 2020-01-30: 42025 = 1673 kWh.

[Pocster]

1 hour ago, AliG said:

The Powerwall 2 guarantees 70% of its capacity at 10 years so I think this covers this.

 

When I ran the numbers on the Powerwall 1 it didn't make economic sense as it would wear out before it paid for itself.

 

Even now I think I would probably need a Powerwall 3 with longer lifespan and higher capacity to work properly in my circumstances. Presumably the touted "million mile" battery would work well in a Powerwall.

I double checked with my installer and indeed Tesla themselves - no power wall 3 is in development ( not of course ignoring that could change )

There isn’t much cause for one here in the UK - you can usually only use 3.8kw as limited by the grid . So larger storage not really helpful . Even if pv panels came out tomorrow at 40% efficiency ( as opposed to 20% today ) the benefit is limited - charge your battery faster especially in summer . 
As Tesla the only real improvements for a power wall 3 would be a physically smaller unit and of course a lower price .

So the biggest hurdle is actually the grid .

[SteamyTea]

4 minutes ago, Ed Davies said:

I drive a diesel van and heat with oil

Do you run the van on heating oil?

My car uses about 20,000 kWh a year of Tesco's Finest.

[Jeremy Harris]

4 minutes ago, SteamyTea said:

My car uses about 20,000 kWh a year of Tesco's Finest.

 

If that were its electricity consumption, then that would cost me about £1,630 in off peak electricity.  Interestingly, it's equivalent to roughly 80,000 miles a year in my car.

[Barney12]

57 minutes ago, AliG said:

The same goes for washing towels after one use which I reckon accounts for about 25% of our laundry.

 

Do you live in a hotel?  

[SteamyTea]

17 minutes ago, Jeremy Harris said:

it's equivalent to roughly 80,000 miles a year in my car.

And a bit over 20,000 in mine.

Or, at £1.25/litre £2,250/year.

 

Now shall we compare depreciation, by car is worth about a tank of fuel.

Edited February 10, 2020 by SteamyTea

[K78]

I think early adopters will regret it. Battery technology is moving fast driven by the motor industry. 
 

I have no doubt in the near future we will all have batteries in our homes. They are getting cheaper and more efficient. 

[Jeremy Harris]

What's the ratio of transport energy use to house energy use here, then, in terms of probable CO₂ impact?

 

Our house uses around 4,500 kWh/year from the grid, my car uses around 2,000 kWh/year from the grid.   We probably also use around another 3,000 kWh of potentially zero carbon self-generated electricity.

[SteamyTea]

7 minutes ago, Jeremy Harris said:

We probably also use around another 3,000 kWh of potentially zero carbon self-generated electricity.

Really just offset until the country has an true excess of very low carbon generation.

 

But I use about 5 MWh/year for the house and 20 MWh/year for the car.

Only 1 car here, and one person.

Edited February 10, 2020 by SteamyTea

[AliG]

11 minutes ago, Barney12 said:

Do you live in a hotel?  

 

Jus with two women, one of whom is American.

 

They value their convenience over most things, so I got serious tried yesterday because I had not put the dishwasher on as I believed I could get more stuff in it whereas they just wanted what they needed to be instantly available. Luckily they do not know how the heating works!

 

I don't know if anyone else has American family, but it really has to be seen how much of an affront saving stuff is to the American way of life.

 

It took my wife a long time to accept that you can figure out how much food people might eat and not just cook twice as much as necessary on the grounds that not to have an excessive amount of food available may make you look tight fisted. Most of them really do have a different mentality. Whenever they come to stay the amount of food and packaging we go through is offensive.

 

36 minutes ago, Ed Davies said:

I reckon the projector alone uses around 1000kWh a year

 

We do not have a smart meter due to being on three phase, so I was looking at various appliances in the house to try and figure out what accounts for our large electricity bill.

 

The washing machine plus heat pump dryer use about 2.5kWh between them per load, so that is about 650kWh a year assuming 5 loads a week(I am not here most of the time so this is a guess). One saving I have managed is putting up a line in the laundry room to hang up sheets and blankets rather than put them in the dryer.

 

The dishwasher uses about 1kWh per load and is run easily once a day, so 350kWh per year. My idea of running it every day and a half would save around 100kWh which isn't that much.

 

So then I started looking at the AV equipment. We have started to use the projector like it is a TV. It is half term and my daughter is in there watching The Simpsons on it. It has a 265W bulb in it and a "typical consumption" of 380W. If it is used 7 hours a day on average then that is very close to 1kWh.

 

The scary one os the amplifier. At full power it uses 1.5kW. Now that would deafen people, but I would guess it runs to a similar consumption as the projector. All the other parts such as Sky Q box, ethernet switch, routers, CCTV use very little electricity in comparison to these, but it all adds up as most of these items are on 24 hours a day. Because they run 24 hours a day I had checked them and found their consumption is pretty low. The PJ and Amplifier caught me out.

 

[Jeremy Harris]

9 minutes ago, SteamyTea said:

But I use about 5 MWh/year for the house and 20 MWh/year for the car.

Only 1 car here, and one person.

 

So similar household energy consumption (although there are two of us here), but a massive difference for personal transport energy use.

 

I'd guess that, for most people, personal transport uses significantly more primary energy than anything else.

 

Really need to turn both the house and personal transport numbers into primary energy to make a fair comparison, though.

 

 

[Ed Davies]

46 minutes ago, SteamyTea said:

Do you run the van on heating oil?

 

No, and it would not be plausible English to parse my sentence that way. My neighbour at my house site runs one of his vans on the road on red diesel. Before anybody squawks, yes, it's legal. I think it doesn't have an MoT either and that's legal, too, but I'm really not sure if I've remembered that right.

[Barney12]

47 minutes ago, AliG said:

I don't know if anyone else has American family, but it really has to be seen how much of an affront saving stuff is to the American way of life.

 

It took my wife a long time to accept that you can figure out how much food people might eat and not just cook twice as much as necessary on the grounds that not to have an excessive amount of food available may make you look tight fisted. Most of them really do have a different mentality. Whenever they come to stay the amount of food and packaging we go through is offensive.

 

I'm absolutely with you. My brother (English) married an American and they now live in the US (Just across the river from the Big Apple in New Jersey) and the entire mentality is different. Its not just energy, its "consumption" in every sense. From food, clothing and services. Its the last one that amazes me the most. The list of "men" they have for various tasks is staggering. The "pool man", the "laundry man", the "garden man", then there is the "garden decorating man" (Come on you know! The guy you get to put the lights and fancy stuff out for holidays and haloween etc). Oh then there is the cake man (every celebration needs a dedicated cake), the catering man (you cant have a party without caterers). When I was there last month my 8 year old nephew had his birthday party which 12 kids were invited. I sh*t you not it involved 5 different subcontract trades. ? Including the guy that turned up with a 30ft gaming truck containing every console and game known to man and a dozen or so big screens (inside and out).