With energy prices rising again, the UK taxation (or cost of living) or some other excuse will see the power price rise eclipsing most other countries in the world. It is odd that some countries have a £0.08 kWh price where as the UK will see prices around 3 times more.
For £237.25 you pay you get nothing in return, and with the average home paying £1,485 on top of this for power, which in those other countries is just £405 per year. You may think that there is something wrong and you would be correct.
You can do something about this with solar and you can reduce your power bill and free up cash for other costs, you should keep in mind the return times and costs of solar. At RenewSolar we try to make solar affordable and have a very short return time. Fortunately there are other countries and suppliers that feel the same way and therefore working together we can and do provide the lowest cost options.
Will going off grid work?
Going off grid with your power is a bit of a commitment. the UK is not the best country for year round solar and you will struggle in winter. You will probably want a generator but it will still costs less than grid power and you actually will make massive savings. You would be in charge of your power, and that is a responsibility you need to consider.
A “decent” off grid system is likely to cost around £10,000 which includes all costs for the initial year. but over the life time of the system your annual power bill is going to cost you £689. 9 or £1.82 per day.
that’s £6.80 per day from the grid as a comparison.
A “good” off grid system is going to cost around £5,000 which is around £333 per year on power, and half of the cost is almost covered in not paying the standing charge.
It used to be the case that being on the grid and going off grid was tightly bunched in costs between the two that it hardly made sense to go off grid, sure in the short term there is a cost to do so, but when we looked at a longer term the savings stacked up. Not by a small amount, but about the amount to buy a house.
What are the best solar systems?
Solar power systems come in various types, ones that work with the grid are grid tied and are parallel. this includes hybrid inverters. For most grid tied system go off when the power is off and you only save what you can use, therefore it can be a little diluted.
Scale of solar makes a different, bigger is not better and there are a few sweet spots where you can get the best value for solar and yourself. Remember that solar has to work for you and that adds complexity or costs and hitting the solar wagon hard will just be a waste of your money.
There is not real “best solar system” to have if you target a budget, or what ever principle you have decided to use to pick out what the best is, value, cost, yield, are all types of values that you can pick. But then there can be compromises.
Grid Tied Micro.
Micro inverter + 2 solar panels. A little 800w solar system that does not take up much space.
Without mounting system, that costs around £231.00. producing 572kWh pa which is around £137 yearly saving. You would get more than this, but thats how we do the math, a but its pretty good estimate.
Why micro?
Small and simple. the idea here is that through the day time for most of the year, you could produce up to 800 watts of power, its likely to be around 650w, or about £223 during the summer. You wont save that much as your day time load will likely be lower than the power you produce. The micro solar system off sets the bill and costs, but at the same time your only saving what you use. If your day time load is 250W and your making 650w, you are only saving 250w. but those savings will add up.
Making solar work?
to make solar really work for you you have to have a battery system. a hybrid.
When it comes to the battery, the excess solar, like the micro inverter would make goes into the battery and is stored for you to use later. So with this type of solar installation, you save what you make, rather than use.
Buying a hybrid system is costly, for most I would suggest the 15 kwh battery, though for the purpose of this example i will use the 5.12 kwh battery. This battery would give you 5kwh of power after the sun has gone down, so to make the system work effectively you would need to have enough solar to charge the battery back up, and for the day time loads. this means that the solar runs the house and charges the battery during the day and you run from the battery at night.
The 5.1 kwh battery is currently £750 meaning that you would need to drain 3, 125 kwh of power from it to replace the grid charges to break even – that means reach zero again, and that accounts for 625 cycles (1.7 years).
Having solar panels, and we will use 450w solar panels with mounting system, is around £500 and gives you 2700 watts of solar power.
So we can do the math’s, that’s a summer peak of 21.4 kwh per day. This has an annual day average of 10.8 kwh ( about £2.60 per day) and to reach zero again that’s 192 days.
The cost of a certified inverter is around £1200, though you could drop to a £450 hybrid inverter. The lower power inverter is what we will use here. as it makes the best sense and pound for pound, it makes perfect sense to pick that one.
Hybrid solar.
3.6Kw inverter, 5.1kwh battery and 2.7kw solar
£1,700
As you can see the cost for the hybrid solar installation is 7 times that of the micro inverter. so lets crunch the math on this. the grid power would be 7,083 kWh.
Solar yield is £463 or 1,929 days/5.28 years
Battery save is £438 or 3.38 years
Meaning the system pay back is 1.8 years
Wow you say? the ROI is so low. That is because the the total costs are not included; you have to consider how things are installed and the cost to install them.
lets say you have our standard installation, which is roughly £450.
You may luck out and scaffold costs just £130.00
Your installation location is just near the meter, so the costs are low, you have a new breaker, and your isolators and cables adding another £225.00
This adds £805 on top of that cost bring the total to £2,505 /10,437 kwh and now are zero point is 2.34 years. If you need trenching and costly cables this will jump up that zero point.
Profit/ savings on hybrids solar installations?
To work out the profits or the saving you will get from solar, you have to look at the life span of the system and what the system makes and the zero point, as the first years of solar installation the system is not making any profit or saving. The hardware and installation of your solar has to pay off the cost to have the system first before you actually make any savings at all.
As a ball park figure we use 10 years as a system life, as the we air on caution, but £9,010 will be the saving, you could save £13,500. You could on top of this sell excess power and gain an additional £5,907.52 giving you a “profit saving” of £19,407.52.
ATS and OFF GRID solar.
ATS is an off grid and on grid system. These can vary in how you want to make them work, but you can split loads having some on grid and some off grid parts of the home. You use the grid as a back up and as your generator. Using the grid still means that you will have a standing charge unless you go off grid.
Off grid hardware tends to be lower priced as it had not had to pay member fees for parallel solar hardware. You could get 10kw inverters for less than half of a hybrid inverter. How much power you need will vary per home and by this I mean Peak loads and the total power use.
ATS.
ATS stands for automatic transfer switch, this allows you to switch between sources automatically while keeping a load on ( give or take a few milliseconds) this allows you to have grid on one source and solar on the other.
Off grid.
Off grid is a fully independent power solution for homes and businesses, you would not have a grid connection at all and you make your own power grid. Your home would be wired as any other normal home, but rather than having a meter you have your inverter providing power to your home.
It is a good idea to have a “plant room” that is built to house your energy systems so that any noise is away from other people as well as batteries and generators.
While your are off grid your on your own, and while this seems to be fully appealing, you have to maintain the entire system and have redundancy, as no one is going to fix your system for you.
Typically we recommend dual inverters and have one as a standby / load balance.
lets run some numbers here to see the costs and the saving of off grid power and I will have to detail a “how to” on off gridding in another post.
To run independently you need to have redundancy, so for part one that’s going to be 2 battery banks and 2 inverters. so we are looking at around £5,000 giving you 30kwh and 12kw respectively.
We would lower the average calculation point for the solar array to give you the best yields and covering more power from solar over the year, so 7.5kw of solar is required, that’s going to be 14 of our big solar panels with a cost of £1,134.
You will also want a 6kw generator which can run a load or charge the battery or both.
The redundancy here is two inverters, should one fail the other can take the load. If both inverters have a fault then you can run from the generator this adds around £2000
For most of our clients going off grid relates to the cost to have a grid connection, usually within the £20,000 range, therefore this system cost falls way below the connection cost. but at £8,134 we can still run the numbers.
Connection cost -£
Standing charge -£2,372+
Annual power saving £2,628
Total saving £29,000 that’s 3.5 times the investment and excludes connection costs which could double that figure. Remember we are using conservative figures here, but you could see a return of around £40k over a ten year period.
Whats your view?
there are many way to lower your bills and to have solar, if its money saving or environmental agendas, then solar can work for most people as long as you have space to do so. but not all solutions are the best and what works for one, may not work for another.
whats your views? whats your ideal solar solution?
share your view in the comment section below.
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