Navitron Renewable Energy and Sustainability Forum

Energy/Electricity Storage and Use/Grid Connection => RHI (Renewable Heat Incentive) => Topic started by: cypher007 on February 03, 2014, 02:31:46 PM



Title: solar thermal worth it? (when used with PV and immersun)
Post by: cypher007 on February 03, 2014, 02:31:46 PM
wondering if solar thermal is worth it? would I need a MSC installer? whats the RHI like?


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: Stochengberge on February 03, 2014, 07:30:58 PM
Given what I know now, the availability of things like Immersun and the constant delays in the solar thermal RHI for domestic applications, I probably wouldn't have bothered with thermal and would have max'd out the PV on the available roof space.
PV heats your water & you get the FIT payment as well. Bargain!!!

SB.


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: cypher007 on February 03, 2014, 08:59:00 PM
that's one big tank 300ltr's. is it just for dhw? how many people are tanking showers there? on a serious note im wondering if a 3kw element could heat that much water? anyone.


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: regen on February 03, 2014, 09:10:28 PM
300 litre is fine when its being supplied by a wood burning stove as well which inturn supplies some or all of central heating.  Just for hot water then 100 to 150 litres is good but make sure the immersion element is installed near the bottom of the tank. It will probably max out during periods of high generation particularly with a 4kw pv system.

Last year our 4kw which feeds a 300 litre store maxed out on about 5 occasions.  The beauty of the thermal store is it allows you to combine different heat scources simultaneously and then feed both central heating and hot water at the same time.

Regen


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: cypher007 on February 03, 2014, 09:24:49 PM
just noticed you've got 1kw and 3kw immersion heaters. didn't know you could get a 1kw element, this solves the exporting some lecy at peak times problem. how are they fitted on the tank both at the bottom? how does the immersun feed them?


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: jeff wode on May 28, 2017, 06:55:20 PM
ive seen 3kw immersion heaters fed with 110v from a yellow site transformer making it pretty much a 1.5kw immersion, and the beauty of it is that 3kw heaters are cheap as chips and available everywhere. i thought it was a great idea, although it helps if you have the yellow transformers kicking about the placee.


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: Countrypaul on May 28, 2017, 07:48:52 PM
ive seen 3kw immersion heaters fed with 110v from a yellow site transformer making it pretty much a 1.5kw immersion, and the beauty of it is that 3kw heaters are cheap as chips and available everywhere. i thought it was a great idea, although it helps if you have the yellow transformers kicking about the placee.

If you feed a fixed resistance load at half voltage you only get 1/4 the power out of it not 1/2. Halving the voltage also halves the current so 1/4 of the power, so most likely the immersion ran at 750W rather than 1.5kW.


Title: Re: solar thermal worth it? (when used with PV and immersun)
Post by: jeff wode on May 29, 2017, 01:50:22 AM
ah right, i was only going by what the guy told me in passing.