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Hi,

We're just about to get our EV hopefully in a few weeks. In addition - we're also aiming to have an air source heat pump within a few months instead of gas, and we already have solar PV. So there's a few factors going on that can be optimised here!

We're planning to go for an octopus agile tariff. I know there are things like the 'ohme' smart cable that tie in with the octopus agile tariff to charge when it's cheap - but that doesn't make use of the excess solar thats feeding in to the grid. Or we could get something like the zappi or the openenergymonitor.com system, which can monitor excess solar power, but doesn't know about the agile tariff (as far as I know).

But does anyone know of a system that can handle both solar PV and an agile tariff?

For the heating, we'll try and program the thermostat so it warms the house before and after peak tariff times and goes off during peak times. I've found a thermostat that can hook into the octopus tariff too - but we'll probably just try to program it manually to start with.


The other option I can see is investing in a battery as a way of making sure we can make the most of the solar PV, and avoid the high elec pricing times. It looks like Moixa battery has 'intelligent' software to try do this. But it could take while to pay back the investment in the battery - it maybe cheaper to just let the solar power flow back into the grid for now.

Does anyone have any suggestions / experience in setting up / running a system like this (car charger + heating + solar pv, agile tariff)?

Jon
 

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Leaf 30kWh, Outlander PHEV
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Zappi I was told will support ToU tarrif though firmware upgrade soon (maybe it has already happended)

Ohme is planning PV diversion but it will need additional current sensing unit but I do not have any specific info.
 

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Leaf 30kWh, Outlander PHEV
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I agree though battery returns take a while.

I am personally planning to pick up a Solar Diverter to heat the water with excess electricity. Even the payback on that is very long. As some point I will put up more PV and excess will be worth storing.

It depends on how much you generate. Our daily usage is approx 50kWh and that costs anywhere from 3-4 GBP. If you generate half as much, buying battery would make sense.
 

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Discussion Starter #4
Zappi I was told will support ToU tarif though firmware upgrade soon (maybe it has already happended)
Ohme is planning PV diversion but it will need additional current sensing unit but I do not have any specific info.
Interesting - I'll ask them for latest info on this!


I currently use a solar diverter to heat the hot water, and we could keep that. That works well just now - 1:1 elec heat over using gas. But if we have an ASPH heating the water at a 1:3 ratio - it would be nicer to feed the excess solar in the car
 

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Just going through the same dilemma at the mo. We just moved to Agile, have solar PV and contemplating ashp (hoping the new green loans and rhi can be combined) and batteries next (thinking prices should keep coming down but something like a pylon tech setup looks just about affordable maybe!).

As above zappi and Ohme are about to do tou and solar respectively. (At least I keep hearing).

I've gone for the zappi as it seems to compliment the use of batteries and other sources and help manage those as well as charge the car.

Bit unsure on the ashp though. I keep reading that solar PV is a good compliment but surely heating is generally required in the non generating times in winter so I'd need batteries too to make the most of the PV system to power the ashp. Have I missed something?.
Do the lower running temps mean the ashp needs to go on earlier in the afternoon to compensate for a slower heat up and therefore make use of the sun (if it's out) or lower priced electricity before the 4-7pm peak.

I suppose ifbI work from home more and more in winter I guess it'll of course be nice to know that cold sunny days would mean free (ish) heating.
 

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Our hardware supports this and I have the exact setup (less battery) at home already.

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Leaf 30kWh, Outlander PHEV
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Our hardware supports this and I have the exact setup (less battery) at home already.

Sent from my SM-N976B using Tapatalk
Do you have any preferred installers? What about OLEV grant?. I do need a to second charge at some point and something with PV diversion and ToU would be nice

Sent from my SM-G973F using Tapatalk
 

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The other option I can see is investing in a battery as a way of making sure we can make the most of the solar PV, and avoid the high elec pricing times. It looks like Moixa battery has 'intelligent' software to try do this. But it could take while to pay back the investment in the battery - it maybe cheaper to just let the solar power flow back into the grid for now.
The batteries we currently install can handle solar PV and TOU, and we're looking to source a new version soon that can also do Agile.
 

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Do you have any preferred installers? What about OLEV grant?. I do need a to second charge at some point and something with PV diversion and ToU would be nice

Sent from my SM-G973F using Tapatalk
ChargedEV are best established.

PV Diversion and TOU / octopus agile already supported.

Overview here:



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Bit unsure on the ashp though. I keep reading that solar PV is a good compliment but surely heating is generally required in the non generating times in winter so I'd need batteries too to make the most of the PV system to power the ashp. Have I missed something?.
Do the lower running temps mean the ashp needs to go on earlier in the afternoon to compensate for a slower heat up and therefore make use of the sun (if it's out) or lower priced electricity before the 4-7pm peak.
Our ASHP will heat the DHW from the solar PV during the summer mostly, just ensure that it is timed to heat during the day not at night.
In winter the solar PV contributes little to the power needs. Heating generally has 2 opposite trends, fast heating when you need it vs thermal store and warm houses. Underfloor heating is a prime example of thermal store, it has to stay warm, an ASHP works best as a a thermal heat store, run it most of the day at an efficient temperature. You can then set it up to switch off for the 16.00-19-00 period as everything is warm n cosy. In autumn ours stops at 23.00-06.00, but with below 4c it just runs all of the time.
Great system, beats gas, our home is modestly insulated detached solid wall house, it works excellently, but it has to be designed right, big radiators, efficient ASHP, and warm home.
 

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Thanks ralkbirdy, sounds semi positive. Quite enjoy looking and learning about these new technologies and it's something I'd like to build on over time. Sounds like batteries might help in some ways, if it's not storing solar PV they may just be charging through the night at favourable rates to use for the ashp in the day maybe. Though agile night and off peak day rates don't seem massively apart at the mo.

We have a 1970's built detached house that has cavity wall insulation to the front and rear (in the extensions) and just needs the sides doing now. I was thinking of adding a bit more to the existing 270mm insulation in the loft to help there too. Otherwise I was hoping to use current radiators which were all overspecified really and we only ever have them set at around half power.

I've not really got my head around the best option for water heating yet so I need to look into that more. We don't have a cylinder at the mo but I had considered it for solar diversion purposes. We have an airing cupboard but not sure if the floor is sturdy enough to take a tank big enough for a growing family of 5.
 

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I've not really got my head around the best option for water heating yet so I need to look into that more. We don't have a cylinder at the mo but I had considered it for solar diversion purposes. We have an airing cupboard but not sure if the floor is sturdy enough to take a tank big enough for a growing family of 5.
I considered solar water heating, but with an ASHP, simply having as much solarPV as possible will give good power for the ASHP in summer, we have 14 panels. It only takes about 1 hour for 2 people. The rest of the day you get solarPV at a decent rate to run washing machines or charge a car. A Zappi is great for this, my car gets plugged in early on, when there is enough power it charges, then has a break while the ASHP is running.
The AHSP has an efficiency of about 4, so very economical.
When looking at ASHP, ask about the power to do DWH, how it manages defrost cycle, and how noisy it is. Our Stiebel Eltron was comparatively expensive especially compared to a new gas boiler, but it is quiet, effiecient, heats dhw to 60c, but they are very large, especially including the hot water cylinder.

 

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What you want to do with ASHP is use Heat Batteries. Have a look at it Sunamp. You can charge then up using multiple sources including Heat pump or electricity.

No need for large storage tank

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Good point on the sunamp, I had looked at these but may give them a rivisit. Did you DIY install?

That strives eltron looks lovely and quiet yet efficient. Price looks a bit rich but the economics might work out. Think I have a lot of research to do by the looks of things. Starting to realise that the ashp will need to run a lot in advance if when we'd typically need it and generally keep the house warm. It's a fairly typically built recentish house but nothing like passive or airtight. I was hopeful using our oversized radiators might work out ok with the ashp. Looks like we use about 10,000kwh per annum for space heating (set to 19.5degC) with our gas combi at the mo. Not sure how that translates into ashp size required, I guess it will depend on building heat losses.
 

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Good point on the sunamp, I had looked at these but may give them a rivisit. Did you DIY install?

That strives eltron looks lovely and quiet yet efficient. Price looks a bit rich but the economics might work out. Think I have a lot of research to do by the looks of things. Starting to realise that the ashp will need to run a lot in advance if when we'd typically need it and generally keep the house warm. It's a fairly typically built recentish house but nothing like passive or airtight. I was hopeful using our oversized radiators might work out ok with the ashp. Looks like we use about 10,000kwh per annum for space heating (set to 19.5degC) with our gas combi at the mo. Not sure how that translates into ashp size required, I guess it will depend on building heat losses.
I personally haven’t used Sunamp yet. I know a few folks on Twitter who have. Also talked to C Sunamp a few times asking various / stupid questions


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Here's an example of the agile integration on our kit. (Shown from history screen)


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