Solar Power-is it worth it?

landyv8

OK shoot me down! I am back on my home PC and checked my figures, that I record each week in terms of oil usage.

I did state appox £450, well it is about £330. !!!

As stated boiler is off for ~5 months

Heating just water uses on average 20L per week @ ~0.70p L

=£280

The approx 1 more months solar gain either full days or part heating i.e solar to ~40 then boiler upto full = £56

Total £330

My system is not piped up wrong, it is a boiler house burner heating a dedicated fuild circuit which passes through the radiators and can divert to the DHT coil. Tank is 250L with second coil for solar.
Hot water that exits taps is NOT same as water passing round/ radiators/heating coil.

Yes my bills are large, but the house is a larger than average 5 bedroom house.

Rather than trusting the goverment etc (who can not be trusted) Why not listen to people who do have these systems in.

I paid £3000 for the system so looking (at current energy prices) just under 10 years payback.

But with increasing costs of energy this is coming down all the time.

You can look at other savings, like boiler/burner life. Effectivly only using it for 6mnths of the year has doubled it life.

I have no oil leaks and burner is servcied every 12 months. It is just a large house.

I am sure for a normal 3 bed semi size savings will be about half i.e what you orginaly stated, but my bils are twice a 3 bed semi so my staving are justified.

I hope you can see that I am not selling solar systems ( I have not conveced any of you lot;-) ) I am just statng my facts.


PS my prefred energy source (heating and electricty) is Nuclear! i.e I am not a tree hugger.

radcon

landyv8 wrote:

My system is not piped up wrong, it is a boiler house burner heating a dedicated fuild circuit which passes through the radiators and can divert to the DHT coil. Tank is 250L with second coil for solar.
Hot water that exits taps is NOT same as water passing round/ radiators/heating coil.

I never said it was the same water.

landyv8 wrote:

So if we wanted hot water in the summer (for example) we would have to have the central heating on! Not good. All radiators are on thermostatic valves except two which are just basicaly high tec pipes with metal fins. So these rooms would get hot.

If these rads/fin tube convector's get hot when the DHW Tank is calling for heat - and therefore hot water is flowing through the coil in the tank, then your system IS piped wrong.

Your CH and DHW should be able to call for, and get heat separately. This maybe is part of the large oil bills when your Boiler is on. You are trying to heat up rooms and your DHW tank at the same time, instead of just a tank of water.

Also check the setting on your cylinder stat as they aren't the most reliable things in the world.

Like I said, I think your saving isn't down to solar, it's down to your boiler not being on. If your system was functioning correctly I don't think you would be claiming such large savings.

Anyway - enough for now as it's friday night! Enjoy the long weekend

Cardew

landyv8 wrote: »

OK shoot me down! I am back on my home PC and checked my figures, that I record each week in terms of oil usage.

I did state appox £450, well it is about £330. !!!

As stated boiler is off for ~5 months

Heating just water uses on average 20L per week @ ~0.70p L

=£280

The approx 1 more months solar gain either full days or part heating i.e solar to ~40 then boiler upto full = £56

Total £330

My system is not piped up wrong, it is a boiler house burner heating a dedicated fuild circuit which passes through the radiators and can divert to the DHT coil. Tank is 250L with second coil for solar.
Hot water that exits taps is NOT same as water passing round/ radiators/heating coil.

Yes my bills are large, but the house is a larger than average 5 bedroom house.

Rather than trusting the goverment etc (who can not be trusted) Why not listen to people who do have these systems in.

I paid £3000 for the system so looking (at current energy prices) just under 10 years payback.

But with increasing costs of energy this is coming down all the time.

You can look at other savings, like boiler/burner life. Effectivly only using it for 6mnths of the year has doubled it life.

I have no oil leaks and burner is servcied every 12 months. It is just a large house.

I am sure for a normal 3 bed semi size savings will be about half i.e what you orginaly stated, but my bils are twice a 3 bed semi so my staving are justified.

I hope you can see that I am not selling solar systems ( I have not conveced any of you lot;-) ) I am just statng my facts.


PS my prefred energy source (heating and electricty) is Nuclear! i.e I am not a tree hugger.

Firstly, have you any connection with Generys or SolarKent? Your explanations have exactly the ‘stamp’ as that firm – “cost of new tank to offset cost”, “boiler lasts twice as long” etc etc.

Anyway!

What on earth has the size of your house got to do with Domestic Hot Water(DHW)? Size of the property has relevance to space heating, - ie Central Heating but not DHW.

So your statement that the savings would only be 50% of yours for a 3 bed semi is yet another nonsense. If you and your family lived in a tiny apartment or a mansion you would still use the same amount of Hot Water.

If heating just your DHW uses 20 litres of oil a week that is over 200kWh a week so approx 10,500kWh a year. So with your 95% efficient boiler you are still - apparently - using well over 3 times as much energy to heat your DHW than the average property.

Hot water that exits taps is NOT same as water passing round/ radiators/heating coil

.

As a statement of the obvious that really takes the biscuit! Have you ever seen the black oily fluid that goes round the heating system and through the heat exchanger coil?

So let us turn to your amazing solar system. In less than 5 months(20 weeks) it has generated(apparently) the equivalent of 400 litres of oil. That is just over 4,000kWh of energy, and you were able to use all that hot water!!! Or do you just leave the hot tap running!

One hell of a solar system it must be. 4,000kWh in under 5 months Wow! Most people including all the independent tests for the Government get 1,000kWh in a year!

Incidentally why can the Government not be trusted on their figures? Do you think they are trying to deter people from using solar?

Now for a quick economics lesson on payback time (ROI). You paid £3,000 for your system(I expect that doesn’t include the cost of the new HW tank – I bet the old one was full of scale;) )

To borrow £3000 at 6% will cost you £180 a year in interest(or loss of interest on savings). Now in the real world you are not even going to save £180 a year or anything like that amount. So your payback time will be never!!

Well as you said in an early post, you have "put it in simple terms for simple people."

Well I readily admit I may be simple, but I still think you are wrong in just about every respect; so perhaps you could run it by me again! Some plausible explanations would help greatly.

mech_2

Landyv8:
Surely you understand why we're sceptical? You still haven't given us a clear enough idea of the system you're describing. How large is the solar collector? 2 sq. m? 5? What is its orientation exactly? How many people live in the house? 2? 6? 12? How thoroughly did you establish your previous usage? You said you only moved in last year!

I agree with radcon. If you were previously heating rooms when you needed hot water, the solution would have been a lot simpler than a solar hot water system.

Incidentally, you say we should trust you rather than the government, but at least government funded studies are transparent about how they reach their figures. First you say you're paying 45p a litre, the next you're paying 70p. One minute you're saving £450 in summer plus additional winter savings, and the next you're saving £330 in total.

I think the quality of the data is lacking, that's all.

Cardew

Mech/Radcon,

The cause of Landy's plumbing problem is that he has an Aga, albeit he doesn't use it.

I have previously written about this issue.

If you have any additional heating source(Aga/Baxi back boiler/wood burner) feeding into a oil/gas boiler CH system you have a safety problem. You cannot isolate this third source of heat with a valve as you have a potential explosion on your hands. Should the Aga be lit and the valve not opened, with nowhere for the boiling water to go - it explodes.

Thus you can have a backpath for hot water(even when CH is not on) via the Aga water jacket to radiators.

Landyv8,

Despite your technical knowledge, and if you don't mind taking advice from a simple person, check out your plumbing very carefully before you ever switch on your Aga to heat water.

With a new tank, and new 95% efficient boiler, you just might have a problem if the plumber has not taken the above into consideration.

Sol00

Going off topic, does anyone know if the wind turbine is worth looking into for electricity?

EXPAT_2

Forget wind turbines, they are not viable at all, unles you have on e the size of E-on's.

I highly recommend GSHP's & evacuated tube solar systems...now they really do work!

amtrakuk

I've had a few looks at getting some solar panels but seems to have mixed feelings, some people say it doesn't pay for itself some swear by it, saying its saving them 100s a year

amtrakuk

EXPAT wrote: »

Forget wind turbines, they are not viable at all, unles you have on e the size of E-on's.

I highly recommend GSHP's & evacuated tube solar systems...now they really do work!

Yeah I heard wind turbines aren't really worth it. I guess thats one of the many reasons why B&Q has stopped selling them. also had a mate who said he was rejected planning permission for one :mad:

moonrakerz

amtrakuk wrote: »

I some swear by it, saying its saving them 100s a year

Those that "swear by it" usually have a vested interest - ie: they're selling them ! OR, they realise they have been conned and are too proud/embarrassed to admit it.