advice please,add a cylinder to combi to utilise solar pv

[jackthom]

Hi tony thanks for showing an interest, you might find this hard to believe as i did, you get the feed in tarriff whether or not you use the electric thats been generated,
I'm just looking at ways to cut the bills.

But if you go on to use that generated energy, for which you've received 22p, aren't you then charged ~15p per KWh.

Surely it would be better to pocket the entire 22p and use it to burn lots of relatively cheap gas?

(I hope I haven't misunderstood the feed in system totally. )

 

[Norcon]

Solar twins MD (Barry Johnston) is a dork. Had his butt well kicked on here...
http://www.navitron.org.uk/forum/index.php/topic,5902.15.html

A biologist if you don't mind turned solar installer!

 

[numnutss]

Hi tony thanks for showing an interest, you might find this hard to believe as i did, you get the feed in tarriff whether or not you use the electric thats been generated,
I'm just looking at ways to cut the bills.

But if you go on to use that generated energy, for which you've received 22p, aren't you then charged ~15p per KWh.

Surely it would be better to pocket the entire 22p and use it to burn lots of relatively cheap gas?

(I hope I haven't misunderstood the feed in system totally. )

the feed in tariff is crazy, you get paid for what you generate(the feed in tariff is14.9p a unit now and going down again in April), and you can use as much of it as you like for free and still get paid for every unit you generate.

 

[numnutss]

What you are trying to achieve is very similar to the Alpha solar smart, which heats the water with solar thermal where you want to use PV and an immersion heater and use a vaillant boiler instead of the Alpha boiler, no reason why you couldnt

http://www.newaveheating.co.uk/alpha-solarsmart.php[/QUOTE]

hi Ian, yes thats pretty much what im looking at doing but i dont understand what theyve done to get around the WRAS guidelines for legionaires found here http://www.wras.co.uk/Preheated-Water.htm

and more in depth here http://www.wras.co.uk/PDF_Files/Preheated_Water_Report.pdf

is the risk of legionaires different in an unvented cylinder?

 

[ianmcd]

In the Alpha system the water in the cylinder is stored between 65C to 70C so the legionella part of stored water is satisfied, the only way I think you could get around it is to have a fast recovery cylinder on your system with a control that brings the stored water above 60C for the period of 1 hour every 24 hours using heat from your combi boiler, you would have to calculate how much energy (Gas) this would use I wouldnt have thought much to be honest, and compare this with your HW usage to see how much of a saving all this would be

http://www.alpha-innovation.co.uk/custom/upload/pdf/solarsmart 100 inst-user 01.pdf

 

[numnutss]

In the Alpha system the water in the cylinder is stored between 65C to 70C so the legionella part of stored water is satisfied, the only way I think you could get around it is to have a fast recovery cylinder on your system with a control that brings the stored water above 60C for the period of 1 hour every 24 hours using heat from your combi boiler, you would have to calculate how much energy (Gas) this would use I wouldnt have thought much to be honest, and compare this with your HW usage to see how much of a saving all this would be

http://www.alpha-innovation.co.uk/custom/upload/pdf/solarsmart 100 inst-user 01.pdf[/QUOTE]

This sounds good, if it was set to boost the temperature at around 5 o'clock when the sun has had time to do its best and before we use most of our hot water, any hot water not used would be stored until the next day, but how would I set it up?

 

[Norcon]

Try this...
http://www.esbe.eu/gb/en/applications/solar/solar-8

Example 8.

There is a small risk of legionella in domestic hot water solar systems if the system has not been at 60c once a week for an hour.
Copper is a natural biocide and lowers the risk also. As said in the earlier link, applying L8 to a domestic system is just nuts.

You'll find plenty of scare mongering on the net from those with vested interests.
Parts of Solartwins system had rubber hoses fitted. Would be surprised if he's still in business.
Personally I see little benefit to solar if your gonna heat the cylinder to 60c every 24 hours.

 

[numnutss]

Try this...
http://www.esbe.eu/gb/en/applications/solar/solar-8

Example 8.

There is a small risk of legionella in domestic hot water solar systems if the system has not been at 60c once a week for an hour.
Copper is a natural biocide and lowers the risk also. As said in the earlier link, applying L8 to a domestic system is just nuts.

You'll find plenty of scare mongering on the net from those with vested interests.
Parts of Solartwins system had rubber hoses fitted. Would be surprised if he's still in business.
Personally I see little benefit to solar if your gonna heat the cylinder to 60c every 24 hours.

So if i were to somehow set it up with a cylinder with a coil connected to the heating side of the boiler and make it heat upto 60c once a week that would do it, how would i set that up?
Thanks Joe

 

[Norcon]

Try this...
http://www.esbe.eu/gb/en/applications/solar/solar-8

Example 8.

There is a small risk of legionella in domestic hot water solar systems if the system has not been at 60c once a week for an hour.
Copper is a natural biocide and lowers the risk also. As said in the earlier link, applying L8 to a domestic system is just nuts.

You'll find plenty of scare mongering on the net from those with vested interests.
Parts of Solartwins system had rubber hoses fitted. Would be surprised if he's still in business.
Personally I see little benefit to solar if your gonna heat the cylinder to 60c every 24 hours.

So if i were to somehow set it up with a cylinder with a coil connected to the heating side of the boiler and make it heat upto 60c once a week that would do it, how would i set that up?
Thanks Joe

S plan from your boiler but it would be easier to set the timed boost function in the immersun invertor.

Intasol Combi Solar Diverter Valve is another valve you should look at.