If your neighbour
in the street does that make it right for you too as well?
Solar panels still worth it?
- Thread starter JamiePattison
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in the street does that make it right for you too as well?
We have 4KWp of solar panels which came with this house when we bought it. We had to replace the inverter about a year later as it packed up - cost £660. We added 15KWh of batteries to the system a little over a year ago and also moved across to Octopus Agile. Our house is oil heated, but with hydronic underfloor in most of it.
The Solar is on a relatively old FIT. We get 22.8p per KWh for everything we GENERATE plus 7.14p per KWh deemed export on half of what we GENERATE. What we try to do is use as much as we possibly can as we still get paid even if we consume it. Due to where we live and the orientation of the panels, this gives us about 6 to 7 hundred pounds a year of income plus, by storing much of it in the battery, it means that we don't need to buy that electricity.
I've looked into the benefits of a heat pump countless times and the big thing that puts me off is the quality of the system design and installation capability. There are far too many installers who have spent their lives installing large gas boilers and are now trying to do the same with heat pumps. General accepted practice is to install a heat pump roughly equivalent to the heat loss of the house and not much larger than it. So, if our oil boiler dies, we will only look at a heat pump then. let's hope that there is an equivalent of the BUS when the time comes. Get the SCOP wrong and a heat pump becomes a very expensive proposition.
So, is solar worth it? For us, if your system allows you to store and load shift what you generate then it may be a reasonable proposition. It really isn't a decent proposition if your motivation is to use what you can at the point of generation and export (for reward) the rest. It's almost a given that many of the export tariffs are going to get more and more mean as time passes, especially as the UK has an excess of green power at some times and a huge deficit at others (especially in the winter).
It's really hard to measure a payback time for us because, as with our previous house, we changed the way that we used power based upon the system we had. In our old house we tried to use power when the sun shone (as we didn't have batteries) and were careful what we used at other times. In this house, now, it's all about acquiring the energy cheaply, be it via solar or at low cost periods with Octopus Agile, storing it and using it as and when needed. Home Assistant automations also help massively with that.
I don't think I would ever consider buying solar without a method of load shift (such as a battery or a suitable EV).
The Solar is on a relatively old FIT. We get 22.8p per KWh for everything we GENERATE plus 7.14p per KWh deemed export on half of what we GENERATE. What we try to do is use as much as we possibly can as we still get paid even if we consume it. Due to where we live and the orientation of the panels, this gives us about 6 to 7 hundred pounds a year of income plus, by storing much of it in the battery, it means that we don't need to buy that electricity.
I've looked into the benefits of a heat pump countless times and the big thing that puts me off is the quality of the system design and installation capability. There are far too many installers who have spent their lives installing large gas boilers and are now trying to do the same with heat pumps. General accepted practice is to install a heat pump roughly equivalent to the heat loss of the house and not much larger than it. So, if our oil boiler dies, we will only look at a heat pump then. let's hope that there is an equivalent of the BUS when the time comes. Get the SCOP wrong and a heat pump becomes a very expensive proposition.
So, is solar worth it? For us, if your system allows you to store and load shift what you generate then it may be a reasonable proposition. It really isn't a decent proposition if your motivation is to use what you can at the point of generation and export (for reward) the rest. It's almost a given that many of the export tariffs are going to get more and more mean as time passes, especially as the UK has an excess of green power at some times and a huge deficit at others (especially in the winter).
It's really hard to measure a payback time for us because, as with our previous house, we changed the way that we used power based upon the system we had. In our old house we tried to use power when the sun shone (as we didn't have batteries) and were careful what we used at other times. In this house, now, it's all about acquiring the energy cheaply, be it via solar or at low cost periods with Octopus Agile, storing it and using it as and when needed. Home Assistant automations also help massively with that.
I don't think I would ever consider buying solar without a method of load shift (such as a battery or a suitable EV).
That is one of the big downsides to all this newer technology and complexity is fine providing the standards match otherwise reliability suffers. Something like an open fire or woodburner will keep you alive even when the gas and electric fails but now most modern systems need electricity so leave you in the cold. It can be a massive investment for small rewards but for many they see free electricity without considering the initial investment and will often tie you to living there for longer terms rather than selling to move.
Jacob
What goes around comes around.
I wondered if it would add value to the house, but unless it was in good order and you could show bills and prove the benefits, it might have the opposite effect.
If your COP is better than around 3.5 the heat pump should be cheaper to run. We got an ASHP installed in October and have managed a COP of 4.1 in a partly insulated old farmhouse. Then there are various cheaper electricity tariffs where you can save a lot more on top. Also add in some spare PV production to run it especially in the shoulder months. No option for natural gas here anyway so it was a no brainer for us
As to adding value, it very much depends : panels added sympathetically to a modern house may put off some but may be an attractive proposition to others. Panels on an old house, especially if they detract from kerb appeal, seldom add value - generally the opposite.
With our previous house, a 1950's, they really had to be on the front of our house, in a line just below the ridge. I think they were about neutral for many when it came to selling. With the house we have now, a period house, c. 1970's, with a nice frontage and a slate roof, they are stuffed away on our garage/workshop block quite a few metres from the house and facing away from the road, thankfully. This does compromise power generation somewhat but it still retains main house kerb appeal.
Interesting - which supplier did you use for the installation? (feel free to PM). If we go down that road I would want to find somebody who knows what they are doing.
Eshmiel
Established Member
To use solar or batteries or any other self-generating electricity supply, if you're truly disconnected from the grid, is certainly possible. If you're actually still connected to the grid, which has just gone down (supply failed due to a fault "out there" somewhere) you need an arrangement that prevents you exporting to the grid, as otherwise some electrician up a pole or in a sub-station might be fried by Jacob e-juice, as that electrician is joining up the wires again.
Such protection-for-the-grid generally comes in the form of a UPS (Uninterruptable Power Supply) box that does actually disconnect you from the grid before allowing your electrical devices to use your electrical generator and/or store. It stops you exporting any electricity to the grid when its "down" but allows your house to continue using electricity from your solar/battery.
Some systems of solar/battery come with this built-in and some require an additional "box" to perform the functions.
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Whether solar/batteries and the like are "practical" depends on how much you use electricity and for what. For me, its very practical as everything is run with electricity, even the car. No electricity means no light, cooking, washing machine, heat, hot water, cold water (the "well" needs an electrical pump to extract from way down there) sewage (a pump takes it from a collection tank up 10 metres to the mains pipe) and no workshop machines. There is a wood burner but its only been lit 4 times in 6 years - to demo it rather than because it was needed for heat. I don't want to gas meself, do I?
For those with just a need for light, cooking, washing machine but no big consumers like heating and hot water, solar and a battery can still be cost effective. It allows you to store and later use not just solar electricity but cheap overnight electricity. For example, I pay just over 6 pence per kilowatt hour for night time electricity, loaded into a house battery, car and even running the washing machine on a timer during the 7 hour cheap period - but only through winter as most of the year the solar (used when generated and also stored in the batteries for later) is sufficient for everything. The daytime rate is 24p per kilowatt hour - 4X the night rate. But I never have to use daytime electricity.
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In every individual case, you need to make a cost/benefit analysis. The benefits can be just the monetary saving but there are several others that are not cash-based: being greener; being more protected from the increasing number of grid outages; not having to use polluting and health-damaging stuff like woodburning and gas; having a degree of protection from large supplier fuel price hikes. You can also run an e-car for little or no fuel cost.
It all takes a capital outlay. But it seems better stuff to buy than a foreign holiday or spending hundreds a time to go and see some slebs twanging three chords on their guitars.
And, in the long run, you will get your money back in just about every case. If you die before you do, why care? You can't anyway, as there'll be no "you" to do so.
HamsterJam
Let’s take it apart to see what’s inside….
Thanks @Nail
I have narrowed it down to one optimiser/panel by shielding each panel in turn using a large sheet of cardboard until I found the one that made no difference.
Of course this doesn’t identify whether it is the panel or optimiser that has failed so I need to get up on the roof and do some measurements and/or swap optimiser over with one from a working panel and see whether the fault moves.
I could reach from the top of a ladder to shield the panels but I need to get onto the roof and behind the top edge of the panels to access the optimisers.
Not entirely down the drain as you'll be benefitting for years to come. But i agree there isn't enough cash incentive vs outlay. What size array did you go for?
I'm still offered the same deals including standing charges and unit rate so it's not true in my case.
The 10 year life cycle isn't strictly true either, you generally have a 10 minimum life cycle with the guaranteed effectiveness of the panels. I think mine is a 0.25% loss per year in effectiveness so I have a guarantee of 97.5% effectiveness by the end of the 10 years. What those guarantees will be worth will of course be debatable.
HamsterJam
Let’s take it apart to see what’s inside….
Most solar installations are ‘grid tied’ which means they are connected in parallel with the main electrical supply.
To prevent them back feeding into the grid during a power cut, it is a requirement they shutdown when there is no mains power detected.
There are some inverters that will produce power in the absence of an incoming mains supply but these have to be isolated from the grid in order to do so.
An east west split is actually quite good in performance- where I lived previously had an east/west split (3kw in each direction) plus a nearby neighbour had an identical system installed literally two days later (by the same crew even) but all facing north... fitted in 2016...
That's the east PV array and the north thermal panel, the west PV array is on the other side, and an overhead shot from google earth...
In practice- although his had a higher midday peak, ours started earlier, and finished later, with a lower, but longer midday peak- and the end result was both gave exactly the same total daily generated kWh per day....
Except in overcast conditions...
There we usually had a LOT more generated per day in comparison to his all north facers... (by several kWh a day- usually 5-7kWh a day more than his 'ideal' facing panels!!!)
We paid $4000Au at the time of install, and it was fully paid off by the time I moved out in 2020...
Of course my 'new' place is solar powered- in fact there's no mains connection at all- I spent under $18k Au all up for a 18kw array (72 250w panels) 12kw inverter, 20kWh battery bank, that paid itself off from day one (I could have doubled the systems size, and it still would have been cheaper than getting a new 8kw grid connection onto the property ($42k Au)- and no bills or blackouts lol
A lot depends on how techsavy you are- a gridtie (with its attendant high costs and low feedback rates) has pretty much become a nightmare, many home owners here have gone batterybacked gridtie systems instead, where your panels recharge the batterybank, and only export after they are full, and the houses uses are covered basically by the battery bank, with only occasional 'dips' onto the grid ie off-grid, but using the mains grid as an 'emergency generator'...
If the panels are from one of the reputable Tier one suppliers, then it doesn't matter who the installer is, the panels themselves will be covered by the manufacturers warranty...
Most panels these days have a 25 or 30 year output guarantee, usually 85% to 90% plus after that time period, and yes they do last that long (and far longer) in just my family we have a system installed in 1997 (mums), 1999 (my uncles), 2008, expanded in 2017 (lil sisters) and my first offgrid system (still in use at an ex neighbours (1984)- all still right in line with the expected results...
Even the old ones I started using in the 1980's at my first offgrid house- now at my ex neighbours down south- are still well over 70% of their 'as new' output- but considering that the power consumption of the loads has dropped markedly over the years since they were first bought, they can actually still handle the same 'loads' even though their output has dropped by about 25%- lighting at the time was incandescent or ballasted fluro, now LEDs do the same job with the same brightness at 1/10th the power consumption, the TV was a 18" CRT TV that chewed a couple of hundred watts, these days a LED LCD uses about 50w and is huge in comparison lol
Inverters usually have a 8-10 year warantee as well, but actual failures are pretty rare- in practice I have only heard of three failures in family and friends- two from the same storm (lightning strike on the powerlines took out everybody's inverters in the street- as well as many other devices) and the third- well- that was from the floods in Brisbane... inverters tend to not work after being underwater for several days... as in the inverter was mounted on the house wall- and the flood waters were over the gutters of the house....
But apart from that, they do tend to be quite reliable for the better known brands...
Trina are one of the largest panel manufacturers in the world (and been in business over quarter of a century...)
Panasonic is equally well known...
