Air to Water

Water John

Building a good sealed, well insulated house, really as Mick says do the insulation very well. Then your heating costs come down. Wheras my 25 yr old house costs 1500/2000 per year in heating oil. They well speced house now will come in at around if not less than €500 per year.
Would do UFH and HP if I was at it now. If well sealed also put in Mechanical Heat Recovery Ventilation (MHRV), its not an optional extra for a well sealed house.

murphaph

I've had the heat on for the first time in our new build and it's just quality. It's such an even temperature and no draughts. We've a low temp system, currently running at around 27 degrees so you can't really tell that the floor is the heat source. It doesn't feel warm to touch but the house got up to 23 degrees yesterday with 8 degrees outside temp so I flattened the heat curve slightly. It'll take some time to get it set up just right though.

Water John

There are weather compensating thermostats. Some say they are tricky. I have no experience of them.

If you got a well sealed , insulated house then why would you spend the guts of 15-20 K on a heat pump ? perhaps a wood pellet stove is the most cost effective solution ?

Perhaps even night storage heaters with night rate electric is even more viable, if you have such a well insulated house it shouldn't cost a lot to heat on night rate electricity V the cost of a heat pump, it's ridiculous.

murphaph

Deleted User wrote: »

If you got a well sealed , insulated house then why would you spend the guts of 15-20 K on a heat pump ? perhaps a wood pellet stove is the most cost effective solution ?

Perhaps even night storage heaters with night rate electric is even more viable, if you have such a well insulated house it shouldn't cost a lot to heat on night rate electricity V the cost of a heat pump, it's ridiculous.

That's a valid point and I know plenty of people who subscribe to the "well insulated + gas boiler" model. In our case (being 150m from the road) the gas main would have been a few grand to lay and we'd have to install electricity regardless. We also want (at some future point when the sums really add up) to install PV on our roof (which intentionally faces SSW @ 45° and around 110m² of surface area to allow us to install a "decent" system that even in November/February can do something.

So our HP is part of a speculative strategy really. Might not pay off if energy costs plateau.

Edit: We have no night rate electric available here.

murphaph

murphaph wrote: »

That's a valid point and I know plenty of people who subscribe to the "well insulated + gas boiler" model. In our case (being 150m from the road) the gas main would have been a few grand to lay and we'd have to install electricity regardless. We also want (at some future point when the sums really add up) to install PV on our roof (which intentionally faces SSW @ 45° and around 110m² of surface area to allow us to install a "decent" system that even in November/February can do something.

So our HP is part of a speculative strategy really. Might not pay off if energy costs plateau.

Edit: We have no night rate electric available here.

My Partners Parents in baden wurttemberg have 14 Kwp of solar on the roof and this can generate up to 75 Kwh on a good sunny Summers day.

All the excess goes to the grid in Summer and they buy it back at Night rate in Winter for the storage heaters. Their night rate is about 19 C/Kwh which is more than our Day rate, our Night rate is 8 C/Kwh.

They get a generous Feed-In-Tariff for excess to the grid and got a grant for installation.

To make the house air tight with crazy insulation and add a heat pump would have cost almost 50,000 Euro's. Not viable.

They have a wood stove which they use also in the coldest of weather, there's no shortage of wood in Germany and they can get it cheap.

Storage heaters are not as efficient as a heat pump but they are a hell of a lot cheaper than any heat pump and once paid off their energy is essentially free so efficiency isn's so important and once they continue to get a feed-in-tariff after the guaranteed 20 or so years then the Solar should work perfectly well.

Once you get at least the night rate for energy you export then this is really all you need, the grid then becomes your gigantic free battery, only in Deutschland , the cost of Night rate electricity is a lot more than here and in your case there is no night rate..... so need to do your sums, you might get a good rate for exported electricity.

Water John

If the Govn't sets a good feed in tarriff for PV is one problem. We have been waiting a long time.
Secondly, you storage heaters will mean you have to include some other RE source in your build.
The storage heaters will also play hell with your BER rating.

I think 15K is a high price on the HP + UFH.
The kit for UFH would cost 2.5/4K depending. One day for two people to install and one day to commission. Add HP and commission of same. What price, 5K?

MHRV 5K

randombar

What about Vertical GSHP, any idea on pricing for that?

KCross

Deleted User wrote: »

If you got a well sealed , insulated house then why would you spend the guts of 15-20 K on a heat pump ? perhaps a wood pellet stove is the most cost effective solution ?

Perhaps even night storage heaters with night rate electric is even more viable, if you have such a well insulated house it shouldn't cost a lot to heat on night rate electricity V the cost of a heat pump, it's ridiculous.

I didnt like the idea of wood pellets myself. You are tying yourself to a few suppliers who can charge what they like. The system wont be that cheap to install either (what is!).

You also have to keep "feeding" the thing and ordering more pellets and having a suitable place to store the pellets etc. It just didnt sit well with me. Maybe Im lazy!

With a HP, once its installed thats it. It runs 100% automatically all year round. No ordering of anything and the long term goal is to get Solar PV and a FiT to further reduce its already low running costs.

Also, for me, it wasnt just a capital costs decision, you also have to factor in convenience and comfort. I like the idea of underfloor heating as its a consistent heat throughout the house 24hrs a day, warm to walk on and fully automated.

Using gas/oil/storage heaters etc in conjunction with standard rads doesnt give the above. Its more a traditional on/off type system. For instance, you come home early from work one day, the house is cold as you dont have it timed to come on and so you have to wait 30mins while the boiler kicks in. You dont have those kind of issues with HP's and UFH.... the house is ALWAYS at your desired temperature and the running costs for that comfort are quite low. I was willing to pay extra for that comfort. Each to their own of course.

All the above is assuming a new build. Not sure its viable as a retrofit.

murphaph wrote: »

We also want (at some future point when the sums really add up) to install PV on our roof (which intentionally faces SSW @ 45° and around 110m² of surface area to allow us to install a "decent" system that even in November/February can do something.

So our HP is part of a speculative strategy really. Might not pay off if energy costs plateau.

Edit: We have no night rate electric available here.

I'm with you on that. Similar strategy in my eyes too. My "grand plan" is to drive as much of my life on electric and then generate as much of it myself as possible cutting out as many middlemen and suppliers as possible. Electric heating, electric car, electric robot lawnmower.....

Just need a decent FiT now to complete the plan!

On the night rate electric comment... there is no such thing as "not available". Its available everywhere, you just tell your provider you want it.

The problem with heat pumps is their shocking cost and if it brakes after warranty and if it dies after 10-15 years, you've paid a very high price to heat your home. At least storage heaters are relatively cheap by comparison to heat pump.

Having to have a heat pump for regulations is a disgrace, they'd want to give a very good grant to compensate then we'd all have one.

It's equally shocking that storage heaters might effect the BER of a home if it's mainly being powered by renewable energy or significantly so. Yes understand the BER calculated the Kwh cost per Sq meter or something like that but it should also take into account renewable energy.

Yes you got to load a wood pellet stove but that can be once a day, the cost compared to HP is still far less.

The Government are being very smart ordering the cost of all this onto the Home owner and giving no compensation.

In would not like underfloor heating due to the constant changing of our climate, it could be 12 degrees one day in the middle of January and 3 degrees 24 hrs later etc, underfloor heating would drive me mental. I don't care if the house takes 30 mins to warm up because I can set the timer. It's never that cold anyway. 500 litres a year for oil is not a lot to spend on heating. Boy am I going to get a shock when we move in November !

murphaph

KCross wrote: »

On the night rate electric comment... there is no such thing as "not available". Its available everywhere, you just tell your provider you want it.

Where we are it's not available. Our regional network operator doesn't offer it.

murphaph

murphaph wrote: »

Where we are it's not available. Our regional network operator doesn't offer it.

German Electricity prices are mad, but I guess someone has to pay for the feed-in-tariff, still in my opinion , it's unacceptable to make poorer people pay such high prices.

Not offering a night tariff is taking the P**s.

KCross

murphaph wrote: »

Where we are it's not available. Our regional network operator doesn't offer it.

I didnt get you were not living in Ireland! Its available to everyone in Ireland.

KCross

KCross wrote: »

I didnt get you were not living in Ireland! Its available to everyone in Ireland.

"Location : Berlin" wasn't a hint ?

KCross

Deleted User wrote: »

In would not like underfloor heating due to the constant changing of our climate, it could be 12 degrees one day in the middle of January and 3 degrees 24 hrs later etc, underfloor heating would drive me mental. I don't care if the house takes 30 mins to warm up because I can set the timer. It's never that cold anyway. 500 litres a year for oil is not a lot to spend on heating. Boy am I going to get a shock when we move in November !

Oil! Ooooil! I thought you wanted to rid yourself of that dirty stuff!

Anyway, HP's have weather compensating controls so it doesnt pump the same heat in continuously. It adjusts based on the outside temperature. The idea is constant temperature in the house which is what you want.

Its very comfortable!

Oh yes, I definitely want to rid myself of oil, going EV was a major step towards that considering driving 30,000 kms a year is by far the highest energy consumer for me, ridding myself of petrol and diesel is saving a tidy sum especially with work charging, yes I have to pay for the car but the savings go towards paying half the monthly payments.

Anyway, I love the idea of heat pumps, as I said I know how effective it is in the car but at current costs it's a hard sell, then add the cost if it only lasts an average of 15 years provided there are no serious issues in that time.

I can't remember if there was a grant for installation of a HP ?

Water John

Like you Cross would like most aspects of my life to go electric.
It will have to also to drive to a carbon neutral economy.

The extra cost for Vertical GSHP is the borehole drilling mainly. There is a model that drills four holes at angles from one point. Don't know if anyone does it in this country.

murphaph

[Deleted User] wrote: »

German Electricity prices are mad, but I guess someone has to pay for the feed-in-tariff, still in my opinion , it's unacceptable to make poorer people pay such high prices.

Not offering a night tariff is taking the P**s.

I personally believe it's because wind energy requires baseload generation capacity (redundancy) and at the same time Germany has committed to decommissioning nuclear. So now we have very expensive electricity.

Anyway...these prices mean PV (eventually with battery) will make financial sense here before most anywhere else I reckon.

air

On the other end of the cost scale from 20k whole house systems is something like this:
http://www.instarom.com/mitsubishi-air-conditioning-msz-hj25va-9000-btu-h-inverter-2956.html
Under €500 including VAT excluding shipping from Romania
Should be possible to have it supplied and installed for around €1000 I'd imagine.
COP of 3.62 and uses 780W.
If located centrally could be used as the main heat source for a well insulated home and could be significantly powered during the day by a big PV array even in winter

murphaph

A single point heat source, even in a a well insulated home is a total non-runner if you value any sort of comfort.

zulutango

murphaph wrote: »

A single point heat source, even in a a well insulated home is a total non-runner if you value any sort of comfort.

They'd work well in these!

air

Someone had better tell all the low energy home owners with nothing more than a single wood stove that they're doing it wrong then I guess.

Water John

A passive house needs little if any heating. A small heat source would be fine.
A house with a lower BER say A3 or B, don't know if a single point source would need to circulated some way?
A bit more than those little fans on can get for on a stove, don't know?

air

The majority of passive or near passive houses have some form of heating for exceptional conditions.
On a less well insulated house nothing stopping you putting in 2 or 3 units, at 500 odd a pop they won't break the bank.

murphaph

In my home I want 20 degrees in the living spaces, 24 degrees in bathrooms where I'll be wet and naked and 18 degrees in bedrooms so I can sleep better. How do I achieve this with a single heat source in my house?

These are DIN values for these kinds of rooms for houses in Germany by the way, not my numbers.

air

Suggest you stick to German forums then.

Water John

Those would be the zoned temp for these rooms, in Ireland too. 21,23 & 18.
Yeah would be difficult from one dry source.
That's the purpose of rads or UFH.

Sadly some people still putting in these systems and only one thermostat. Defeats the whole potential.

air

Or as I suggested you could put a unit in each room.
I posted the links to the system as I thought it might be useful for some people that might not have realised that heat pumps can be retrofitted relatively economically.
One wouldn't need to use it as the exclusive heat source, but with a COP of 3 one could heat the house overnight for less than 3c / kWh in Ireland on night rate which is cheaper than any other fuel source.

KCross

air wrote: »

Suggest you stick to German forums then.

That's a bit harsh. No one has a monopoly on the right way to do things.

KCross

air wrote: »

Or as I suggested you could put a unit in each room.
I posted the links to the system as I thought it might be useful for some people that might not have realised that heat pumps can be retrofitted relatively economically.
One wouldn't need to use it as the exclusive heat source, but with a COP of 3 one could heat the house overnight for less than 3c / kWh in Ireland on night rate which is cheaper than any other fuel source.

Running them at night wouldn't really work though, would it?

Heating the air is very different to heating a concrete slap with a HP. You don't want 23C going into the air during the night.

So,realistically, wouldn't they be running at the day rate, not nightrate?