Considering new install of solar panels and battery in North Yorkshire

[NY13]

Hi all, been lurking for a while and hope I have learned a lot already. I'm thinking of installing panels and battery to help mitigate the upcoming scary energy cost rises and have, so far, drawn the following conclusions. Any criticism/observation is very welcome and I am particularly looking for advice on how to find a reputable installer that would cover North Yorkshire. Many thanks!

• We use around 7000kWh electricity a year. Heating and water is from a combi-boiler and I don't want to mess with that (or think about an air source heat pump) for now. I don't have a smart meter so all these figures are approximate.
• In theory 1500kWh of that goes in to an EV via a Podpoint wall box, which was installed a year ago. If the car I commute in dies I would probably get a second EV.
• I don't think my roof space would be completely optimal (South/West split with some shading from the West when the sun is low) so I was thinking about 6kW of the best panels I can afford.
• For obvious reasons these days it seems like the best way to recoup costs is to use everything I generate so I was assuming a battery would be a good idea.
• I would hope to generate 4-5mWh per year so hopefully a good chunk of that would go in to the car (it's on the drive 4-5 days a week), some for running the house when we are in in the day and the rest into the battery. I have no idea what size battery I would need so maybe a modestly sized on that could be added to in the future?
• Battery and inverter to be able to supply a reasonable peak power, from what I have read on here more than just 3.6kW
• I am happy to dive in to graphs, spreadsheets and so on so I would like good control over the system in terms of diverting the power where I want it in an attempt to maximise usage/minimise power back to the grid.

That's it for now, many thanks to everyone who contributes to the forum, it's really really useful.

 

[johnb2713]

I went through a similar process, my system installed at the end of April this year.

I have 16 Hyundai panels - 10 x South Facing and 6 x West Facing gives me a total of 6.5kW, Growatt 6kW Hybrid Inverter and a Growatt 7kWh battery. We also have MyEnergi ZAPPI (EV Charger), EDDI (Energy Diverter) and HARVI (Central Hub).

We have the system set to charge the battery from the grid on Octopus GO off peak (00:30 to 04:30 - 7.5p), from 04:30 until the panels start we run on the battery, throughout the day we run on the panels if the weather is good - charging the battery, heating the water and charging the car. During the evening when the panels stop we run on battery again until 00:30 when the GO starts again.

The net result, Octopus suggested we increased our DD from £178 per month to £565 when our tariff ended in April. I downloaded our half hourly readings for the previous year and calculated on the same usage and the new rates that £465 per month would have been the correct figure. since April we have used almost zero peak rate units, a substantial drop in off peak units and we are using electricity for hot water rather than gas. The last 3 months we've used circa £65 per month in electricity. So at the moment were £400 per month better off, obviously in winter time that will not be so good. I am going to add another 14kWh of battery along with 5kW of inverter power to help stay away from peak power rates during winter. The new Octopus GO rates in October will increase that saving considerably.

I have a spreadsheet with all of the 30 minute reading, solar generation etc. If you want a copy of it along with the graphs etc you're welcome.

 

[binky]

Out of interest, are Octopus accepting battery installations without MCS certificate?

 

[johnb2713]

Out of interest, are Octopus accepting battery installations without MCS certificate?

I have no idea on that one.

I have written to my DNO regarding my new battery addition and they have no problem with that, I'm not sure how Octopus are affected with it?

 

[Murdoch]

Op log on to the octopus app and set the DD to the value you want

 

[johnb2713]

Op log on to the octopus app and set the DD to the value you want

That doesnt resolve the issue of the price hike though does it?

 

[Murdoch]

That doesnt resolve the issue of the price hike though does it?

No but it does allow you to control your DD which is very positive

 

[johnb2713]

Sorry, I really don’t see your point. If electricity has gone up by 40% how is it a positive thing to keep a lid on your DD? Sure you can pay a lower amount but at the end of the day you still have it to pay.

 

[Murdoch]

Sorry, I really don’t see your point. If electricity has gone up by 40% how is it a positive thing to keep a lid on your DD? Sure you can pay a lower amount but at the end of the day you still have it to pay.

If the cost has risen by 40% then your DD need only go up by 40%

 

[NY13]

@JohnB thanks for the reply, super helpful. I can see me getting something very similar to what you have now but probably without the EDDI/immersion heater for the time being, though that may appear in phase 2.

I am inferring from what you are saying (correct me if i'm wrong)

• The extra battery capacity will help you leverage the cheap electricity at night from Octopus Go in the winter when you generate less yourself? I had a look at Octopus this week and I can only dream of getting electricity at 7p/kWh at night so I may have missed that boat.
• The HARVI allows you to control the flow of electricity between the panels or grid and Zappi/battery/house from your phone, even away from the house, like a bond villain?
• I may need to replace the podpoint charger with a Zappi for full control. I would hate to do that as it's only a year old but if I have to I have to. The podpoint is mounted inside the garage so looks are not important.
• Your savings will only get bigger in October and then January unless the government intervenes massively so you will be looking at recouping the investment in around three years? If so that is crazy.

Many thanks for the info. Did you research for installers on the various websites or did you get someone recommended?
Thanks everyone else too for the tips. I take the view that the more I know the better.

 

[up_north]

@JohnB

• The extra battery capacity will help you leverage the cheap electricity at night from Octopus Go in the winter when you generate less yourself? I had a look at Octopus this week and I can only dream of getting electricity at 7p/kWh at night so I may have missed that boat.

Octopus Go is still showing 7.5p per kw/h for four hours.

 

[johnb2713]

@JohnB thanks for the reply, super helpful. I can see me getting something very similar to what you have now but probably without the EDDI/immersion heater for the time being, though that may appear in phase 2.

The hot water cylinder is effectively like a battery, stores energy in hot water. EDDI is great because at time you may have a full battery and say 600w being exported. EDDI will control the immersion heater and even though you have a 3kW element it will just divert the 600w to it meaning you harness all of your energy and export nothing.

I am inferring from what you are saying (correct me if i'm wrong)

• The extra battery capacity will help you leverage the cheap electricity at night from Octopus Go in the winter when you generate less yourself? I had a look at Octopus this week and I can only dream of getting electricity at 7p/kWh at night so I may have missed that boat.

• 
  Correct, the shorter days and lower sun in winter will seriously affect the PV generation. I'll PM you re Octopus shortly
  
  

  [*]The HARVI allows you to control the flow of electricity between the panels or grid and Zappi/battery/house from your phone, even away from the house, like a bond villain?

  I can set priorities via my phone so for example tomorrow my wife has the afternoon off, I will set the car charging is higher priority to the hot water.
  
  

  [*]I may need to replace the podpoint charger with a Zappi for full control. I would hate to do that as it's only a year old but if I have to I have to. The podpoint is mounted inside the garage so looks are not important.

  They always have good retained value so you can get a good price for them.
  
  

  [*]Your savings will only get bigger in October and then January unless the government intervenes massively so you will be looking at recouping the investment in around three years? If so that is crazy.

  The figures are amazing but I do religiously download my Octopus data daily, feed it into a spreadsheet and the figures speak for themselves.
  

Many thanks for the info. Did you research for installers on the various websites or did you get someone recommended?
Thanks everyone else too for the tips. I take the view that the more I know the better.

I researched the thing for about 3 months, complete and utter frustration and I couldn't get anyone to talk me at a technical level like why could I not have a 6kW inverter with the export limited if necessary. By pure chance one of enquiries ended up with phone call from the company's technical architect, he really did know his stuff, much of it obvious with a little thought. I will PM you his direct contact info along with other information.

J

 

[NY13]

Octopus Go is still showing 7.5p per kw/h for four hours.

Yes, you are right. I called them (I have no smart meter) so the process would be to sign up to a standard Octopus tariff, get one of their engineers to install a smart meter and then I could switch to Go. Probably worth it with the caveats that it is electricity only and that sometime between Friday and 1st October the unit rates will certainly rise. Still might be worth it though as we have an EV and a programmable charger.

 

[johnb2713]

Yes, you are right. I called them (I have no smart meter) so the process would be to sign up to a standard Octopus tariff, get one of their engineers to install a smart meter and then I could switch to Go. Probably worth it with the caveats that it is electricity only and that sometime between Friday and 1st October the unit rates will certainly rise. Still might be worth it though as we have an EV and a programmable charger.

Have a look in conversations, I've sent you some info there.