Advice on heating system for a new build

newgroom

Hey all,

I'm getting close to starting a new build, planning is drawing to a successful finish. Now my one big 'head-wrecking' decision is my heating system for the house. I'd appreciate some advice.
It's approx 3,200ft2 new build, on a large rural site. So I've all options available from geothermal to air source to oil. Ideally I'd like underfloor throughout, in the open plan living area there'll be a stove as well as in the sitting room too.
I attended the self build show last Saturday in Dublin and even though I got quotes for air-to-water and geothermal, I also got a lot of opinions stating that if I was having a high standard of insulation etc and with the high capital costs of heat pumps then an efficient economic oil boiler would be best option........I'm so confused.........any suggestions? Thanks

BryanF

What does your provision BER suggest?

mosesgun

It's a tricky one. I sold renewable heating systems for a few years during the "good times". Majority of customers were in your position. From personal experience I found that overall people's experiences with a well specified geothermal heat pump we're generally positive. Air to water heat pumps, although cheaper due to no ground works required don't have the same COP (coefficient of performance) as a ground source geothermal heat pump. We used to sell a direct evaporation pump manufactured by an Austrian company called Neura. If you look up <the forum charter> you'll find lots of information. There are loads of them running throughout the country and generally customers were very happy. (I've no affiliation with this company anymore) but that heat pump had the best figures available at the time.
Insulation is the key though for you. Put as much money as you can afford into this. I can't overstate the importance of this.
A good interim solution might be to put in excellent insulation, underfloor heating throughout and a relatively inexpensive oil boiler. See how much it costs for a few years and if its expensive then perhaps look at a heat pump or wood pellet boiler.

newgroom

BryanF wrote: »

What does your provision BER suggest?

I havent done my BER yet but the standard of insulation is high, 0.13 for walls, 0.58 for windows, HRV system installed. I'm just thinking that for the amount of heating that will be required possibly an oil boiler with solar panels might do. Although will I achieve enough renewables for Building Regs? I feel electricity tariffs in this country aren't low enough for running these systems, we should have a lower tariff for running heat pumps to encourage people. A green rate as incentive?

Rushy Fields

I am also interested i heating systems for my new build. I got a provisional BER assessment carried out on my design and put in Geothermal, HRV and Solar panels to meet the new regs. but i'm unsure about the payback on the big capital outlay mainly because the house is going to be well insulated and airtight in that i will not need a big heating requirement therefore not alot of heat required. So why should i invest in such an expensive system in the Geothermal?
Any alternatives/suggestions are welcome.
I am also concerned about the Air to water systems due to the odd cold winters/spring conditions. I just dont know enough about the systems yet so anyone with experience inthis area i would really like to hear from.
Many thanks.

newgroom

nealger wrote: »

but i'm unsure about the payback on the big capital outlay mainly because the house is going to be well insulated and airtight in that i will not need a big heating requirement therefore not alot of heat required. So why should i invest in such an expensive system in the Geothermal?
Many thanks.

This is exactly why i started this thread, it seems to me that geothermal and other heat pumps are pushed onto designers/builders today as if you have to go with them to be greener and they'll save you a fortune in heating bills. The initial capital outlay for a geothermal could be anything up to €20,000 and an air-to-water heat pump could be €10,000-€15,000 (rough estimates). From calculations I've seen you can save approx 50% on heating costs with the renewable systems (at best when installed correctly and used properly) but the amount invested could take 15-20 years or longer to pay for itself in comparative savings if you've a highly insulated, air-tight house with HRV and little heating requirements.
Also the efficiency of these system in cold weather conditions can vary, remember too that electricity prices can rise as well as oil.
Is there any experts out there to shed some light on the subject, it'd be greatly appreciated?

sydthebeat

theres a school of though held by some here on boards that an air to water heat pump is the most economical way to meet regulations. Personally, i dont hold that view.

If i was starting a build today i would be seriously considering a condensing wood pellet type system as my main heating source. Your renewal requirement is met straight away and in fact is well in advance of that is required. Plus, heat pumps are best served with underfloor heating, which is an additional capital cost at build stage. Wood is best suited to a radiator system. Wood is not subject to carbon tax where oil etc is... also electricity has a built in carbon price included at source... so as carbon penalties increase, so does electricity.

Another route to seriously consider is to look at the 'passive house' route where a high degree of detailing and insulation will negate any need for a high cost 'BOLT ON' technological heating system. heating needs can be met with small heating elements in air handling units, by solar means and by stoves.

darragh_haven

Syd boy, you just convinced me of the wood pellet condenser boiler, i've been mulling over it for nearly 9 months. It is the basic and plain worded info that is always the best
And if it goes wrong, shur, i can say "But Syd said...."

sydthebeat

darragh_haven wrote: »

Syd boy, you just convinced me of the wood pellet condenser boiler, i've been mulling over it for nearly 9 months. It is the basic and plain worded info that is always the best
And if it goes wrong, shur, i can say "But Syd said...."

haha, that will be 10% commission please

newgroom

Thanks Syd that was very informative. But can i ask what's the price of wood pellets currently and amount required per annum in comparison to the other systems. I know you need to build in a housing for the boiler and large feeding silo too. Is it realistic too that the price of pellets will increase with oil/gas/electricity??
It's a definite runner though. Are you tied to radiators or can wood/oil/gas boilers work with underfloor?
Sorry for all the questions

BryanF

Consider a log/pellet boiler set-up, more pricy initially but you have the log option in the future. These unit work well with a larger hw tank/ thermal store and can be connected to solar and delivered with UFH - as syd says passive standard detailing is a must to see the real benefits with what ever option you go with.