This doesn't make any sense. The important but is how long does it take to pay off your investment. You don't need to make the most off ir. You just need it to be financially viable.
PV Solar Panels? - worth it?
- Thread starter Ace Modder
- Start date
This doesn't make any sense. The important but is how long does it take to pay off your investment. You don't need to make the most off ir. You just need it to be financially viable.
To be fair a few people have said the same thing, eg make sure you use your washing machine, tumble dryer etc etc during the day make the most of it.
However I agree with you Glaucus our calculations showed us paying it off in ten years. This was based on FIT, Export Tariff and saving on Electricity. Whether this actually happens who knows but somethings got to give the government can't keep cutting the tariff if they want people to take up solar power.
Who actually does their washing at night anyway ? Ironing maybe but most of the things people tell you to do to "make the most of it" you do during the day anyway. Thats just a by-product benefit.
However I agree with you Glaucus our calculations showed us paying it off in ten years. This was based on FIT, Export Tariff and saving on Electricity. Whether this actually happens who knows but somethings got to give the government can't keep cutting the tariff if they want people to take up solar power.
Who actually does their washing at night anyway ? Ironing maybe but most of the things people tell you to do to "make the most of it" you do during the day anyway. Thats just a by-product benefit.
return from solar panels aren't really worth it at the moment unless you really want to be eco friendly.
We've got them and I work from home and for our needs it does cover more than what we need on most bright days although my pc hardware uses less electric than yours and to be fair we're pretty low with what we use anyways.
On an average rainy day you'll struggle to get around 0.2kw per hour which is around what our house uses when my pc is at idle (that's around 0.1-0.15kw/h according to the plug in tester). We worked out we used around 0.1kw/h on our fridge, 2 freezers and other always on stuff like router, phone.
An average day (ie cloudy but still bright) is more than enough for us to do washing, pc, tv etc without it impacting the electric usage.
On a good day you'll get anything up to around 90% of the maximum of your install (3.6kw/h on a 4kw 16 panel system - what we've got) with it being lower at dawn/dusk obviously.
One thing to consider though, we've noticed that our electric shower, cooker, microwave and kettle still draws from electric even on a good day, even though they're all rated lower than 4kw. Some of this is down to the time it's used but your mileage will vary depending on you usage.
We've got them and I work from home and for our needs it does cover more than what we need on most bright days although my pc hardware uses less electric than yours and to be fair we're pretty low with what we use anyways.
On an average rainy day you'll struggle to get around 0.2kw per hour which is around what our house uses when my pc is at idle (that's around 0.1-0.15kw/h according to the plug in tester). We worked out we used around 0.1kw/h on our fridge, 2 freezers and other always on stuff like router, phone.
An average day (ie cloudy but still bright) is more than enough for us to do washing, pc, tv etc without it impacting the electric usage.
On a good day you'll get anything up to around 90% of the maximum of your install (3.6kw/h on a 4kw 16 panel system - what we've got) with it being lower at dawn/dusk obviously.
One thing to consider though, we've noticed that our electric shower, cooker, microwave and kettle still draws from electric even on a good day, even though they're all rated lower than 4kw. Some of this is down to the time it's used but your mileage will vary depending on you usage.
Heh, i've had our display peak at 4.01kWh.
Your shower would be rated at 8-12kW, you'd never cover that with a 4kW solar install. I got caught out by our microwave too, it might say 800w on the front, but it will pull 1300w to do it. Your electric cooker will be another 10kW draw.
Or you know just sell it back to the grid an save 1/3 on the price of the power.
Seek back rate is about 4.4p and purchase rate is about 14p
You don't need to be in during the day you don't even need to use any off it. They will still generally be very profitable over 20years.
By using the power you just decrease the payback time and increase the profit, it however is not essential in the least.
As fir lsgr1 why do you think you need to power everything you have, you don't. Unless you want to be off grid, some posts I this thread are very confusing.
Yeah agree. We are expecting the three incomes to pay off our installation. So we have the FIT + Export Tariff + Saving on electricity bill to go towards paying off the cost of the Solar Panels. As they produce the most when we are not in this will mostly be fed back into the grid and come back to us as Export Tariff. The decision you have to make is do you put the saving on electricity against the cost of your installation or do you just "spend it" and consider it extra cash. If its the latter it takes longer to recoup your investment.
I've seen people mention about heating water.
We had a new heating system installed (unvented cylinder with a rated condensing gas boiler etc) and as such I presume any solar calculations I need to consider gas usage reduction by having an immersun type device to heat the water in the tank when solar generation is available.
Interested to know what further savings this is likely to produce.
We had a new heating system installed (unvented cylinder with a rated condensing gas boiler etc) and as such I presume any solar calculations I need to consider gas usage reduction by having an immersun type device to heat the water in the tank when solar generation is available.
Interested to know what further savings this is likely to produce.
Got other expenses at the moment but I'd like a solar setup, given the only things we have that take power are:
* fridge - more power during the summer..
* CH pump - power during the winter
* pond - power all around the year (pump and UV tube)
* TV - only evenings
* extractor fan in the bathroom - during the morning
* washing machine - during the day or whenever is suitable
Gas is used for heating and cooking. The model of combi is actually water solar compatible (with additional kit I assume).
Typically we use a laptop or a mac mini so power is low.
Our house roof faces south west, our garage roof faces south east. Both get a massive about of sun/light..
* fridge - more power during the summer..
* CH pump - power during the winter
* pond - power all around the year (pump and UV tube)
* TV - only evenings
* extractor fan in the bathroom - during the morning
* washing machine - during the day or whenever is suitable
Gas is used for heating and cooking. The model of combi is actually water solar compatible (with additional kit I assume).
Typically we use a laptop or a mac mini so power is low.
Our house roof faces south west, our garage roof faces south east. Both get a massive about of sun/light..
Soldato
- Joined
- 7 Feb 2004
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I had solar panels fitted in November, I decided to jump in before the rate dropped.
I must admit I am a bit confused when people in this thread have posted about getting more money back selling it back to the grid rather than using it.
I was under the impression it is irrelevant as to what I export back to the grid or use myself regarding payments I will receive, as it is simply assumed that you will use 50% and export the rest back to the grid and all calculations are based on this.
We've changed our daily habits regarding electricity consumption so now washer, dryer, dishwasher etc is done during the day and it has made quite a difference:
After using more electricity every month in 2015 compared to 2014, the panels got fitted in November and immediately our consumption fell, this has continued into this year with February's usage down 29%.
I think this should equate to an approx saving of £200 per year on our Electricity bills.
We also had a Solar iBoost fitted at the time of installation (exports any unused electric to heat the water in the hot water cylinder, once this has reached temperature only then will any excess be exported back to the grid).
In my mind this is our battery, storing excess energy for use later in the day. It feels great all of us having showers in the morning but by evening having a cylinder full of hot water. The savings aren't massive though so payback time is long, I managed to get it supplied at cost (£160) when negotiating the initial system cost.
I have a 3.99KW system and projected output is 3344 KWH/Year, together with my reduced electricity consumption and small reduced gas consumption I am extremely happy with my investment.
I must admit I am a bit confused when people in this thread have posted about getting more money back selling it back to the grid rather than using it.
I was under the impression it is irrelevant as to what I export back to the grid or use myself regarding payments I will receive, as it is simply assumed that you will use 50% and export the rest back to the grid and all calculations are based on this.
We've changed our daily habits regarding electricity consumption so now washer, dryer, dishwasher etc is done during the day and it has made quite a difference:
After using more electricity every month in 2015 compared to 2014, the panels got fitted in November and immediately our consumption fell, this has continued into this year with February's usage down 29%.
I think this should equate to an approx saving of £200 per year on our Electricity bills.
We also had a Solar iBoost fitted at the time of installation (exports any unused electric to heat the water in the hot water cylinder, once this has reached temperature only then will any excess be exported back to the grid).
In my mind this is our battery, storing excess energy for use later in the day. It feels great all of us having showers in the morning but by evening having a cylinder full of hot water. The savings aren't massive though so payback time is long, I managed to get it supplied at cost (£160) when negotiating the initial system cost.
I have a 3.99KW system and projected output is 3344 KWH/Year, together with my reduced electricity consumption and small reduced gas consumption I am extremely happy with my investment.
If you read the article above about the Tesla unit I think this is mainly the issue. The excess electricity is fed back to the grid and you get a small fee about 4.5p/kwh for the trouble. It would be much better if you had some kind of Tesla storage/battery that the excess electricity went to so that say at night when the solar panels are doing very little the electricity is then drawn from your storage battery first till its flat/empty then from the grid as normal. So all what you produce you get to use.
At the moment this option is very limited/expensive so currently its more beneficial to get the export tariff. However when such units are as commonplace as an inverter in the solar panel installation the economics switch the other way round.
Exactly that. If you are getting 4p a kWh selling back to the grid but at night you have to buy it back at 14p then you are still paying 10p if you used the same as what you sent back so it makes more sense to try and fully charge a powerwall and then trickle charge it as you use it and sell back.
We, well I did, looked into powercells for our 4kw setup and to be honest they're just not really worth having because the time when we actually need them (winter) is the time when the sun is the weakest and you have the lowest spare energy so they're never going to fully charge during this time.
It's simply a case of how/when power is used and winter is the time when you end up using the electric the most because the sun is the weakest and the day is the shortest.
With the current prices of the batteries being around 8k and a lifespan of at most 10 years they'd never pay for themselves let alone save you money.
It's not just the cost of the powercell that needs to come down, the efficiency of the solar cell needs to go up so that we can get decent solar power during winter when the powercell is most useful
It's simply a case of how/when power is used and winter is the time when you end up using the electric the most because the sun is the weakest and the day is the shortest.
With the current prices of the batteries being around 8k and a lifespan of at most 10 years they'd never pay for themselves let alone save you money.
It's not just the cost of the powercell that needs to come down, the efficiency of the solar cell needs to go up so that we can get decent solar power during winter when the powercell is most useful
With people changing their energy use patterns to get better gains from their solar panels, I wonder if time-of-use tariffs will change those patterns? I can only see these tariffs being pushed on us by energy companies to encourage energy use at off-peak times.
So 4kW of panels comes out to £2-2.4k. Then you've got the inverter, mouting system, and connection/meter and bits to the house mains. Dont think there's be much saving c.f. a standard £5-6k install, especially as you'd not qualify for MCS payments with build your own panels/install. Also, any more details on build your own?