@chandykris Exactly the same here. We now have 13.5kWh of storage and expect to be doing 2.5-3 cycles per day in the coldest depths of winter. In the milder weather I doubt we will be cycling the battery so hard, but will be topping up 3 times per day from the grid. I'm not overly concerned about the battery - it has an unlimited cycle warranty, it will only really be cycled hard for 8-12 weeks per year and we bought it to be used, not to hang on the wall looking pretty. Plus the more it's cycled, the quicker it pays for itself.

Posted by: @sunandair

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My attention was also drawn to the possible introduction of aggregators - possibly our energy suppliers?

Aggregators have been recognised for many years, and it's a different concept to Energy Suppliers, who buy on the wholesale market.

In it's most simple interpretation, and aggregator is geographically constrained and is acting as a Community Energy 'company'.

It might buy electricity solely from its members (shareholders) and sell only to them.
Or it might also have its own generation and storage assets.

The aggregator pays the DNO for Distribution Use of Service (DUoS) charges,
but can also earn income from them for operating within a 'Demand Flexibility' contract.

For Forum Members in the Midlands, NGED is hosting a Community Energy seminar/workshop day on Thurs 18th Sept at Birmingham.

The event is organised by the Exeter-based Regen group, who invite you to register online here.

NGED provide refreshments, including a buffet lunch.
They will also have relevant staff present, such as Network Planners and Community Energy engineers (yes, they exist within NGED!)

Separately there will be staff from agencies who can help new Community Energy groups to access grant funding for feasibility studies etc.

Note that the day is centred on Community Energy, and does not address:

• national energy policy
• tariff and billing issues
• generation assets being installed by 3rd-parties (commercial solar farms)

Interesting. Good news for Tesla owners?

https://apple.news/AatjZUGtqQNKgMExbJ61rFg

@editor Ok Elon, I have your battery, go on, make me an offer I can’t refuse!😉 Toodles.

My cynical side says this is nothing to do with selling electricity and everything to do with getting a shoe in influence.  

Presumably a way to sell their VPP offering to Tesla owners other than those who have already signed up through Octopus Intelligent tariffs (IOF and IOG).

Presumably it's lucrative for both owner and Tesla, and beneficial to the grid in terms of stability. I've been on Octopus IOF for just under a month and am pleased with the results - no surprises and I'm currently making almost double what I would have made on a standard export tariff, plus I'm helping the grid.

@old_scientist I’ve heard a rumour that OE may reduce the Outgoing Fixed tariff next month; should this happen, I may have to reappraise my present choice of tariff. Toodles.

@old_scientist Can’t help wondering how well the Powerwall will perform when coming up to 10 years of daily thrashing; will that 10 year warranty of 80% capacity still apply to such usage I wonder - or will lawyerspeak weasel words be employed? Regards, Toodles.

Having perused the ‘net, I see that the capacity at 10 years is warranted to 70% not 80. However, I wasn’t aware that …

”Tesla monitors the performance of all Powerwall batteries remotely, and this is part of the warranty process.”

One lives and learns then! Toodles. 

Posted by: @toodles

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@old_scientist I’ve heard a rumour that OE may reduce the Outgoing Fixed tariff next month; should this happen, I may have to reappraise my present choice of tariff. Toodles.

People have been speculating for years that the current SEG rates cannot last. No doubt they will drop at some point, but for now I'm happy to make hay whilst the sun shines.

Posted by: @toodles

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@old_scientist Can’t help wondering how well the Powerwall will perform when coming up to 10 years of daily thrashing; will that 10 year warranty of 80% capacity still apply to such usage I wonder - or will lawyerspeak weasel words be employed? Regards, Toodles.

Before I switched to IOF, my PW3 was typically cycling daily from 100% to 80% and back to 100% again as it powered the house during the evening and recharged from early morning sun.

On IOF it is cycling from 100% down to 20% and back to 100% again. Some days it only recharges to 80%. I think it's pretty healthy to cycle the battery once per day between 80-20-80%

Regarding battery longevity, I was watching a YouTube video yesterday about a guy who bought a Tesla car that had done 266,000 miles and the reported battery health was 76%. If your battery isn't at least 80% 70% after 10 years (with unlimited cycling), Tesla will replace under warranty. How long have you had your batteries, and what is their current capacity/health status?

I'd actually be more concerned with winter usage where I'm going to cycling the battery 3 times per day on the Cosy tariff, not the once per day IOF is doing in summer, and operating conditions will be a lot less favourable in winter.

I wonder if @transparent can advise on the optimum operating methodology? Is it best to cycle daily on a 80-20-80% regime, and how does the charge / discharge rate affect the battery given it can charge at 1.7kW, 3.3kW or 5kW?

* I should also note that IOF is beneficial in summer if you are limited on export by the DNO as the battery will typically discharge to 20% during 4-7pm, and then not recharge until mid afternoon the following day (with all solar exported), so this conveniently leaves plenty of space in the battery all day to store anything that cannot be exported or would otherwise be clipped. This seems difficult to achieve controlling the battery manually as by default excess solar gets stored in the battery before it gets exported, so my battery was typically full by 9:30-10:00am each day. Sometimes IOF will recharge the battery to 80% overnight, but that mostly seems to occur when there isn't much solar forecast for the following day.

@old_scientist I have had the first PW for some 2 years and 8 months, the second for some 2 years 3 months. As to their present capacity, I don’t know as I am too mean to pay a NetZero subscription to use the advanced features which would provide this information. Anyone aware of other methods to gain this performance data from the Tesla PW’s please?

I have also noted recently (due to a firmware update I think) that the PW’s charge to 80% and if one requests higher percentage, a prompt is issued by ‘Granny’ to ensure you really really meant to exceed 80%. Regards, Toodles.

Posted by: @toodles

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@old_scientist

I have also noted recently (due to a firmware update I think) that the PW’s charge to 80% and if one requests higher percentage, a prompt is issued by ‘Granny’ to ensure you really really meant to exceed 80%. Regards, Toodles.

Yes, I noticed that change too. The software really does 'encourage' you to stay in the recommended 20% to 80% SoC range, which I guess will help maintain battery health and help reduce warranty failures.