It can heat your water for the cost of it: £400 for a Myenergi one
Meanwhile electricity is 1.4p difference between export and import with the above.
So it will never break even in that scenario.
Solar panels and battery - any real world reccomendations?
- Thread starter GinG
- Start date
Meanwhile electricity is 1.4p difference between export and import with the above.
So it will never break even in that scenario.
Well it depends on how much hot water you use and how long you expect to have gas available in your property. In the long term gas isn’t going to be available and then there is the whole environment thing you may or may not care about.
That said, if you already have the power and immersion in place, it’s an absolute doddle to fit yourself.
That said, if you already have the power and immersion in place, it’s an absolute doddle to fit yourself.
Man of Honour
Is that over a year? Or over several years? Still when you're spending around £10-12k on a solar system, £400 is frankly such a small amount of money that not to include it seems daft (to me at least).
I'm not on a Go tariff, and the diverter heats my water for cheaper than gas would - so in my instance I think it is worthwhile. My gas consumption has notably lowered. Admittedly not by hundreds of £ but enough to be in a lot of credit with Octopus at the moment (around £1k).
For us it's great as we have 2 kids who prefer baths to showers
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Soldato
Is that over a year? Or over several years? Still when you're spending around £10-12k on a solar system, £400 is frankly such a small amount of money that not to include it seems daft (to me at least).
I'm not on a Go tariff, and the diverter heats my water for cheaper than gas would - so in my instance I think it is worthwhile. My gas consumption has notably lowered. Admittedly not by hundreds of £ but enough to be in a lot of credit with Octopus at the moment (around £1k).
For us it's great as we have 2 kids who prefer baths to showers
If you wind up on Flux I guess it's argument about exporting that 1 kWh and getting paid for it, versus importing Gas to heat the water for less per kWh.
But ultimately if using more clean energy is a goal it's certainly a good thing.
Soldato
I sort of agree but IMO your taking the current situation and using a tariff thats not necessarily available to all
Only recently the BG seg jumped, and 7.5 isnt available on Octopus now.
And FWIW I tried modelling high battery storage and couldn't make it work. IMO the best battery to usage level is around 50-70% unless you have a tiny array.
The problem with solar and energy right now its constantly changing, there isnt a fixed X is best value its 100% dependent on the individual.
There is also potentially agro from SEG jumping and I have heard of people waiting months for BG to get their SEG sorted.
Man of Honour
Well it'll always heat the water before exporting anyway so not sure if that makes a difference?
But yes with flux getting 24p+ per kWh in the summer will make a massive difference.
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Soldato
I think it's just the lost cost, so you put a kWh into the diverter and you don't get paid the £0.20+ for it, but then you could heat it using gas boiler which is either £0.10 or £0.06 if tracker per kWh currently, which should in theory be more efficient.
Man of Honour
What if the water is heated AND I export as well? Then it's win win surely?
Soldato
I mean sure you can do both but hopefully you can see it's an opportunity cost that is lost and the price you pay is the export price per kWh that you could have been paid for?
Your system will well over-produce so there will be a good export figure.
The main benefit of this is the 100% green energy going to the cause I think!
well its unlikely to go anywhere between now and 2050, so suspect anything you buy now will probably die before then anyway.
Man of Honour
Gotcha. Thanks!
Soldato
Precisely highlighting the issue
The optimum is constantly switching, tariff, cost of alternate supply (ie Gas), size of array, batteries etc
Eg should there be a power cut not only will my system continue to function but any excess I generate will go to the water.
Thats some super fringe case, but its irrelevant to most as they would not function the same.
For me it seems most of the year Flux would not be beneficial so for me the best alternate for excess is to send it to my tank
For me SEG needs to be > [cost of gas / efficiency] before it makes sense to export.
Soldato
Yes if you're on Go then diverter wins.
If our suppliers did a 1:1 trade, so every kWh you exported you could import one for free later on, then even the battery would look a bit meh because the grid becomes your battery store (at no cost!)
If our suppliers did a 1:1 trade, so every kWh you exported you could import one for free later on, then even the battery would look a bit meh because the grid becomes your battery store (at no cost!)
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Those that did it are phasing it out. It's fine when there is not much solar and to act as an incentive but its not sustainable. That said our SEG rates are a **** take so I'm not advocating for that either.
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Soldato
Yeah unfortunately thats basically the golden goose for solar generators.
There should be somewhere in the middle really where rates paid to solar owners are guaranteed to match the lowest grid generators price as a statutory minimum in order to protect consumers.
It would probably also need to be time of use (generation) based, but then most UK residential excess generation is going to be when the grid is typically medium or higher priced anyway so thats no biggie to consumers.
Eventually I am sure we will get there. We just have a dumb government going on about stuff like hydrogen to boilers when we should be maximising self generation on things like solar on houses.
Part of that takeup can be supported by ensuring that people get a fair price for excess units (people would be even more likely to max their generation potential if so).
I think Flux may well be a small but crucial step on that journey.
Associate
Whilst most of what MKW says is stuff I agree with, and that would include paying for solar excesses at a fair price, I am in favour of mixing hydrogen in gas boilers.
Solar is a very small player, the most expensive of renewables to install and run, but the real killer is that it is
A. unpredictable
B. Only works during daylight.
C. 70% of the energy it produces is between the spring and autumn equinoxes.
I have unsuccessfully lobbied the government to force new developments into providing more energy efficient homes. The regs only changed last summer and up to that point it was Ok to install rockwall in wall cavities. Further EPC's have not changed in 25 years and are flawed. One big problem is that they measure energy efficiency in a passive way. We have large patio doors on the south side of the house. This is judged by how much energy we lose through them. It complete ignores the 1kw of heat we get per square metre when the sun is shining, which has a significant impact on heating the house in the Autumn and Spring.
Equally unsuccessful was my attempt to get Hampshire County Council to set up a Wind farm offshore financed by the residents who could collectively find the money. For example if you pop down to Tesco's and buy a 8MW Wind turbine, this is about £8 million. Depending on where it was planted (in a farm), it would produce an average of 30-33% of the stated output. At 30% it will generate over £1million/year at 5p/kwh. Allow 20% for its fair share of installation and maintenance and we are left with a very neat return of just over 10%. Half of this could be paid back to the investors and the other half re-invested in long term renewables.
Back to hydrogen. Steel making is one of the most energy absorbing activities we all benefit from. see https://www.nature.com/articles/d41586-022-03699-0
We are all reliant on Hydrocarbons (and Putin knows this as well as anyone). If we tacked Climate Change in the same manner as Covid, there would be a lot more hope for our children and grand children.
Soldato
I am not against hydrogen, IMO its the most logical and attainable form of energy to "make" that is storable, and useable that can be used to soak up some of the inevitable massive surpluses we will see once we start to get close to renewables hitting 100% of demand during off peak times.
However it makes no sense to me, to plan to use that in a domestic setting when we could transition homes far more easily and cost effectively to being soley supplied by electricity.
The hydrogen we generate could be used two fold mainly, for industry, and secondly to replace the natural gas generators (well and the others like limited coal)
Storage is a little more interesting in very large volumes but i am sure we can get that balance correct.
Soldato
The other thing I would add is I expect we will see some planning law relaxed in regards heat pumps (its going to have to be) and small wind generation.
Right now you can have a noisy as hell heat pump but as long as its a certain distance from the boundary thats fine, same with wind generation.
IMO they need to test the noise level from the boundary and set the limitations of that noise level. If things get old and knackered and noisy then they need fixing and should be able to be condemned like we would a faulty gas boiler.
It shouldn't matter if I have one or more heat pumps right on my boundary if its quiet enough that it doesn't not disturb my neighbours.
Same with domestic small scale wind. As long as its not noisy (or dangerous) then it should be able to be anywhere on my land. If it fails noise tests, again, condemn it.
Right now you can have a noisy as hell heat pump but as long as its a certain distance from the boundary thats fine, same with wind generation.
IMO they need to test the noise level from the boundary and set the limitations of that noise level. If things get old and knackered and noisy then they need fixing and should be able to be condemned like we would a faulty gas boiler.
It shouldn't matter if I have one or more heat pumps right on my boundary if its quiet enough that it doesn't not disturb my neighbours.
Same with domestic small scale wind. As long as its not noisy (or dangerous) then it should be able to be anywhere on my land. If it fails noise tests, again, condemn it.
This. I would have got solar a year or two ago had the export rates been good. It would mean little need for a baterry which really pushes the price up. Plus back then prices were cheaper.
Right now it makes zero sense for me to get solar due to silly install prices unfortunately.
This month with the government help I think my bill will be around £30 or less due to getting on Octopus Tracker and the warmer weather.
Guys - this is the house we will be moving into soon - https://www.google.co.uk/maps/place...d-3.2604172!16s/g/11c2dnkbqn?hl=en&authuser=0
The front of the house has a NNW facing roof (if I am reading maps correctly) - does that still give good generation potential? The rear of the house is SSE which I am sure would be better if not for the damned trees at the neighbours side of the property border
I think the roof is perfect to maximise the number of panels although we may have to get neighbour permission as it is facing on to the street
The front of the house has a NNW facing roof (if I am reading maps correctly) - does that still give good generation potential? The rear of the house is SSE which I am sure would be better if not for the damned trees at the neighbours side of the property border
I think the roof is perfect to maximise the number of panels although we may have to get neighbour permission as it is facing on to the street