Solar PV to power "Traditional Central Heating"

mickyduck

Hi I may be completely off the wall but after reading about the multiple systems to "divert unused" power to an immersion heater would it be possible to heat the central heating water using similar technology e g using an electrical element inside a radiator and pumping a system as normal. In theory this would enable heating and water? Maybe the electrical elements don't exist... maybe Im just a bit nuts but seems a simple logical progression from heating your hot water in a tank to heating the water in your central heating system? I am assuming simple logic like the element only heats when the pump is running, would also need a radiator without thermostat that the element / elements were sited in or that would be the only one that got hot!!
Well what do all you experts think?

Martyn1981

Speaking as a non expert, just to point out that electrical elements can be added to some radiators, such as towel rads, so that they can 'do their job' when the main heating is off.

Mart.

mickyduck

Yes did check that those type of electrical elements did exist but to me this seems such an obvious extension to heating a tank full of water I think there must be a reason why no one is suggesting it?

tunnel

Simples, its easier to buy a wattson and a couple of optiplugs,add a couple of oil filled 500w-1kW heaters,then when the sun shines=heat. When it don't your CH kicks in as normal=heat. Adding elements to each radiator seems a rather expensive way to utilise the spare power. At least with the oil filled heaters you can move them around the house as and where they're required(sun permitting)

HappyMJ

mickyduck wrote: »

Hi I may be completely off the wall but after reading about the multiple systems to "divert unused" power to an immersion heater would it be possible to heat the central heating water using similar technology e g using an electrical element inside a radiator and pumping a system as normal. In theory this would enable heating and water? Maybe the electrical elements don't exist... maybe Im just a bit nuts but seems a simple logical progression from heating your hot water in a tank to heating the water in your central heating system? I am assuming simple logic like the element only heats when the pump is running, would also need a radiator without thermostat that the element / elements were sited in or that would be the only one that got hot!!
Well what do all you experts think?

When there is enough energy from the sun to power a central heating system that is when you don't actually want any heating. i.e during the day and the summer time.

mickyduck

tunnel wrote: »

Simples, its easier to buy a wattson and a couple of optiplugs,add a couple of oil filled 500w-1kW heaters,then when the sun shines=heat. When it don't your CH kicks in as normal=heat. Adding elements to each radiator seems a rather expensive way to utilise the spare power. At least with the oil filled heaters you can move them around the house as and where they're required(sun permitting)

Not thinking of adding element to each radiator that's why I said pump would have to be running. House could heat up in the day while I am out "sunlight" permitting when normal heating kicked in it would not be starting from the ambient temp in my house which is cool when Im not in. I run my normal CH thermostat at 18 C and only in the evenings

rogerblack

One square meter of window is equal to about 5 square meter of panel.

legoman62

HappyMJ wrote: »

When there is enough energy from the sun to power a central heating system that is when you don't actually want any heating. i.e during the day and the summer time.

As others have suggested you could use PV and an oil-filled rad...not much use in the summer months agreed. But in Feb, Mar, April, Oct and Nov when the days may be warm, and evenings pretty cold, it would be useful;)

Ectophile

legoman62 wrote: »

As others have suggested you could use PV and an oil-filled rad...not much use in the summer months agreed. But in Feb, Mar, April, Oct and Nov when the days may be warm, and evenings pretty cold, it would be useful;)

That's just what I did today, and several other days recently when it was cold but sunny. But that doesn't happen very often in the UK.

Generally, it's either hot and sunny, or cold and dismal.

legoman62

Ectophile wrote: »

That's just what I did today, and several other days recently when it was cold but sunny. But that doesn't happen very often in the UK.

Generally, it's either hot and sunny, or cold and dismal.

In the months I mentioned it is (sometimes) hot in the daytime and very cold (sometimes) in the evenings. These are the times that you could use excess PV to power the oil filled rad:D

Kernel_Sanders

This would probably only be viable in April, and cool but sunny days in May and June, but you could make all the CH radiators lukewarm using solar PV alone. If your system uses a traditional heat exchanging coil through your cylinder, you could use a 'pump only' setting to circulate the warm water past the immersion heater. This doesn't work for me because my 3kW element is too short, and the thermostat kicks in even when the pump is circulating cooled water near it.