You can hang a few of those 500 series boxes of the end if you like 
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That will weight it down😄
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That’s great, thanks Richard!
I’ve not come across the PVGIS SARAH database before, so also thanks for that.
Just using the defaults, but putting in slightly more accurate azimuth and roof slope values (which is essentially all that the EST calculator was doing) I get effectively the same numbers (withing a few kwh/year). So it looks like the EST calculator is most likely using the SARAH or SARAH2 database. Which is much more reasssuring - so 3,009kwh - which is 3 times what the loop.homes model is showing. Which is a bit bad for loop as they are trying to use the app to sell solar PV…
I might even have a word with Loop…
You do know that’s not how a GSHP works?
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Thats a great outcome Mike for consuming almost all that you generate
We are averaging 71% consumption of solar produced since April
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Very pleased to receive an email from our installers informing us that the date for our installation has been brought forward to 17 Oct. I just need to get the armoured cable laid between the garage and house ready for installation. That will be a bit of an adventure as it’s got to be routed round the garden!
I’m now looking at solar power divertors for the immersion heater.
I’m trying to decide between the iBoost and the MyEnergi Eddi.
They seem to both have their plusses and minus’s.
iBoost plus points, no extra cost for the wireless sensor, and generally cheaper. Additional display unit available which would allow visibility of what it’s doing rather than having to go to the airing cupboard and allows limited control of functions. Downsides - no app or internet integration. Has to be mounted close to the immersion (constraint on cable length).
Eddi plus points - can mount downstairs close to the fuse box as no constraints on cable length on teh output which would be more convenient as display and controls would be more accessible. Integrates to the web so can use an app to display information. Downsides - wireless sennsor additional cost, unit more expensive, hard to get hold of.
Anyone have any views on these devices?
My only view on them is that if you have a battery then I am not sure they provide any significant benefit - other than using surplus generation when your battery is already full, and saving conversion losses to / from the battery. Maybe I am missing something
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We’re not having a battery as otherwise I tend to agree but I anticipate even with our weedy array (just shy of 3kw) we will have plenty to spare. Our base load is between 220w and 400w. If you have batteries it seems best to store in a battery where you can make wider use of any surplus energy rather than narrow it down to hot water.
It does seem that people who have these find that they have very little need for other means of heating water during spring to autumn so I’m hoping we’ll be the same.
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I am going through similar agonies…have put in for planning for a 10kw ground array…I was going to put a small battery in 1st and then relpace it later with homebrew 16kw battery…
I considered the iBoost/battery pros and cons when putting my solar system in earlier in the year (my hot water is currently an immersion heater in a 225l tank, set to heat up overnight when the energy price is lower). Our installer suggested iBoost to us, rather than the MyEnergi one.
In the end we went with batteries for various other reasons discussed earlier in the thread, but also because we are planning a second air source heat pump which will heat the water (with a new tank) as well as heat the remainder of the house that the first one didn’t stretch to. We were waiting to see if our application for the government grant scheme was accepted before proceeding - after a couple of months of waiting, we actually got the green light for the grant earlier this week. So, hopefully within the next month or two we’ll have all heating and hot water from ASHPs…
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Your needs seem very similar to me. My Apollo diverter (not now available) only has the display near the fuse box. Initially this was a bit of a pest, but I found placing some £2 LCD thermometers with the probe at the top and another at the middle of the Tank tells me a lot more about how much hot water I actually have in the tank.
BTW, I have my Immersion set to 65degrees, and the Gas Boiler thermostat on the side of the tank set to 55.
Looking at both those option, I would suggest the Eddi may need a closer look. Firstly it can integrate better to other systems, but more importantly the note below suggest you can also diver to a heater. If its like mine, it would have to be a dumb heater i.e. with no clever electronics added, so the cheap £20 2kW heaters would do well here. You can probably see in my picture above that I have made this simpler by adding a diverter switch, so in the winter, when I have enough hot water, I manually divert the power to an electric heater
BTW, As a general point (again for those without batteries) there is an aim to reduce your base usage as much as possible at night, so I just invested in a pack of 4 Tapo Smart Plugs. Only fitted yesterday, and they are absolutely brilliant. As well as on/off set times, you can also program them to come on/off as an offset from sunrise and sunset. So one is on my car charger, to come on 4 hours after sunrise Monday, and off on Friday 2 hours before sunset. As it was on all the time, this should save a bit. Another is on my Satellite WiFi Mesh device, as no-one needs it on from 10pm to 8am, so that saves another 6.7 Watts. Small amounts, but all helps, and I should retrieve the cost of these devices in a year.
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Thanks for your insight.
Your heater solution is clever, but automation would be nice to have! I wonder how much surplus energy I will have in winter, having a small array so I’m not too sure I would find a heater worthwhile.
I’ve seen the thermometers you mention, they are very inexpensive so I might put a couple in.
I am coming to the conclusion that the Eddi is probably the better one of the two.
Features aside the build quality seems much better. This includes an all metal case vs plastic and passive cooling with nice large heatsinks vs a small fan in the iBoost.
The Eddi can also be expanded with an inexpensive relay card which can allow the gas hot water heating to be integrated too or a destratification pump could be fitted.
Unfortunately the Eddi is in short supply but I have time on my side so may order now in advance of the system being installed.
I have one smart plug on the kettle. We get very cheap electricity overnight (8.5p per KW) which ends at 06:30 so each morning at 06:20 it comes on and boils ready for the morning cuppa’s etc. I estimate that this one measure will save over £20 per year, crazy.
It’s unfortunate that the more privileged such as ourselves are in a position to invest in solutions to save us money. Heaven knows how many are going to manage with the latest increases announced today.
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Sounds like the Eddi is the one
I have the electric heater in the downstairs Hall, and there are quite a few winter days when it’s enough to heat the whole house surprisingly, and if not certainly enough during the day, with a Boiler boost for a cosy evening. Of course you will also have newer panels than my 3 year old ones, so will be even more efficient in the winter, plus you are about 250 miles nearer the equator than me.
You are right about affording to save money. If only there were an option to feed back to the grid for people on a Social Tariff.
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If I might inquire, what company and tariff?
Thanks Phil
It’s Octopus Go Faster.
It’s a beta tariff which you can apply for, it’s a variant of their ‘Go’ product. It’s designed for users of electric cars which until recently wasn’t enforced. We were lucky and got in before this happened. The overnight rate is for 5 hours, we have chosen 01:30 to 06:30. You can have less hours for a slightly lower rate, it depends on what suits you and also what slots are available.
The rate is higher than the current flexible rate at just shy of 40p per KWH. Currently we are averaging 32p between the 2 rates so are slightly worse off as flexibly is around 28p currently. Winter will change this as we will use our A2A heat pump at the rear of our house to boost the temperature during the cheap period and as the tariff is fixed for 12 months we will benefit this winter when prices rise again.
Octopus has an excellent forum too which is worth joining if you are interested in energy efficiency and eco measures.
Thanks for that. I’m patiently wait for the Nissan Leaf E+ (Mid December) and Solar + Tesla Powerwall ((End January). We have the heat pump and a good supply of wood. The fire is going to be used a lot until I get on a better tariff.
The October prices are broadly 52p electric and 15p gas per kWh. Compared with 28p now for electric the gas would rise to 13p. Hoping to run the heat pump at 35C all day until it gets too cold.
Phil
So true - we have just arranged to have roof felt replaced with TLX Gold insulation and 3KW integrated panels to fit in with the tiles as well as a diverter to run an immersion heater. Comes to around £15k so we are lucky to be able to afford it. It cleans out the ISA but holding cash is a mug’s game these days.
The explosion in prices is kind of a blessing in disguise for us (and for the planet, I guess) in that we would have been unlikey to bother with this if inflation and energy prices were the same as a couple of years ago. Our electric bill used to only be around £50 a month as we are fairly light users.
Feeding the surplus in to a pool for a social tariff is a great idea. Surely something has to be done about the electricity companies paying you about 3p a KWH for your surplus which they then sell back for 40p+!
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You should look at Octopus Agile. It’s a variable time of day tariff although due to the current crisis it’s normally at the ceiling price all day of 55p.
What’s more interesting is that the export rate is variable too. For example today they will pay between 41p and 75p per KW depending on the time of day.
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Although it’s not quite the same as other types of privileged consumption. The more people self generate and load shift via batteries etc. to cheaper/greener periods, the less demand there is for more expensive thermal power generation. Which helps to lower the price.
The price problem is fundamentally that we have far too much demand for the available supply (without Russia’s gas) so any reductions that can be made will help. It’s about all we can do as individuals. So spending a load on solar power generation is arguably somewhat altruistic 
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Turned the HiFi off as we had thunder and lightning about midnight. Looked at the Bright App to see how much it reduced the power used overnight and estimated 80-90W. Fridge and Freezer average 60W. Got 90W left to explain! We have old fashioned lamps to indicate appliances are on, broadband hub, the heating system and TVs on standby
If you have a Smartmeter accessible through the DCC the Bright App downloads your 30 minute consumption figures some time later and compiles histograms of usage. It’s quite useful. I suppose the Solar Apps give similar data.
We installed a replacement washing machine and heat pump tumble drier on Friday. The WM was 14 years old. The test wash looked promising and the TD much lower. Five months till the Solar and battery is installed. Six since we ordered.
Phil