Large workshop, very cold, mulling over what might work

[Roger440]

Up until recently, ive tended to ignore solar, gshp, ashp, so im well beind the curve here.

 

But ive a problem that needs solving.

 

Large workshop, circa 2500sqft, was agricultural building. Concrete block infill, steel insulated cladding above that, but only 25mm, cgi roof, unisulated.

 

Previously used a waste oil fired burner, when i had a free oil supply. Though that would do 20-40 litres a day if it was cold.

 

Obviously, insulate. But thats a LOT of  surface area to cover. Probably a seperate post?

 

Much as id like it at 16c, if it was a permanent 10c over winter, id be resonably happy. So ive spent hours looking at solar thermal. The yanks seem to build there own panels, which appeals  because, lets face it, id need a LOT of them. Buying commercially available panels isnt an option. But a week of cloudy days in winter is going to yield little useful heat. I did see @onoff on another thread talking about milk tankers as a thermal store? I cant really get to grips on how long 16000 litres of water, heated during the summer would contribute to my winter heat?

 

Then i though about using ground source heat, but rather than use a heat pump, simply circulate the water from say 10ft down through the slab. If its 8-10 degrees at that depth than surely the slab would be too?

 

As i say, iver perused various, mostly american forums, but still not really sure, what, if anything might do some good.

 

All thoughts, whatever they are, welcome

 

 

[TonyT]

Air 2 Air?

[Roger440]

1 minute ago, TonyT said:

Air 2 Air?

Am i missing something? How does that work if its -5 outside?

[TonyT]

The COP goes down

[Conor]

Just now, Roger440 said:

Am i missing something? How does that work if its -5 outside?

Remember that the celculius scale is arbitrary. -5c air only has a little bit less energy than 5c air. Heat pumps will still extract heat energy down to -20c or so. 

[SteamyTea]

15 minutes ago, Roger440 said:

Obviously, insulate. But thats a LOT of  surface area to cover.

Yes.  You can use all sorts of different materials.  All they really have to do is trap air in small pockets.

 

16 minutes ago, Roger440 said:

The yanks seem to build there own panels, which appeals  because, lets face it, id need a LOT of them

You could fit a secondary, dark coloured tin roof to the south facing side, leave a gap between it and the original (now insulated) roof, draw out warned air with a small fan.

May even work with cheap, clear acrylic sheeting.

Maybe keep an eye on on eBay for cheap PV modules and a few old storage heaters.  Just pump the juice into them and if it gets too warm, open the door.

[SteamyTea]

5 minutes ago, TonyT said:

Air 2 Air?

 

4 minutes ago, Roger440 said:

Am i missing something? How does that work if its -5 outside?

 

Just now, Conor said:

Remember that the celculius scale is arbitrary. -5c air only has a little bit less energy than 5c air. Heat pumps will still extract heat energy down to -20c or so. 

Beat me to it.

 

The refrigerant gas is at around -23°C, so still 18°C to play with.

[Roger440]

1 minute ago, Conor said:

Remember that the celculius scale is arbitrary. -5c air only has a little bit less energy than 5c air. Heat pumps will still extract heat energy down to -20c or so. 

 

I dont think a heat pump is viable here. It would cost a fortune in electricity to run. Happy to be proven wrong, but a 2500sqft 6m high building?

[TonyT]

Destrat fans too then

[Roger440]

4 minutes ago, SteamyTea said:

Yes.  You can use all sorts of different materials.  All they really have to do is trap air in small pockets.

 

You could fit a secondary, dark coloured tin roof to the south facing side, leave a gap between it and the original (now insulated) roof, draw out warned air with a small fan.

May even work with cheap, clear acrylic sheeting.

Maybe keep an eye on on eBay for cheap PV modules and a few old storage heaters.  Just pump the juice into them and if it gets too warm, open the door.

 

What materials though. Had the idea of using washed sheeps wool, bagging it and holding it against the roof with wires. Yanks do this with bagged rockwool. Farmer has a lot of sheep. Couldnt give the wool away last year.

 

Like the ide on the secondary roof? Novel!

[Roger440]

4 minutes ago, SteamyTea said:

 

 

Beat me to it.

 

The refrigerant gas is at around -23°C, so still 18°C to play with.

 

Humour me, are you guys talking air souce heat pumps here?

[Roger440]

2 minutes ago, TonyT said:

Destrat fans too then

 

No idea what you mean?

[TonyT]

Google destrat fan.

 

ive designed  it all for you  already want me to build it too!

[Roger440]

5 minutes ago, TonyT said:

Google destrat fan.

 

ive designed  it all for you  already want me to build it too!

 

Ok, yes, got those at work. Like work, you need some heat to begin with. We never use them at work in winter as there is no heat to move about. But yes, can see benefit, no doubt.

 

Im on a vertical learning curve here!

[TonyT]

Is it possible to subdivide the space up?

workshop office space, toilet space etc all partitioned off.

 

 

[joe90]

Thermal underwear ?

[Radian]

Got 3 Phase? Big Air Con (air to air) isn't all that pricey to buy (£1600 for this 60000 BTU example) Does either heating or cooling.

[JohnMo]

40 minutes ago, joe90 said:

Thermal underwear ?

And a big jumper.

 

Or heat your body, look at motorcycle and walking body warmers, battery powered.  Then you can what ever temperature you like, for way less effort and expense.

[Roger440]

1 hour ago, TonyT said:

Is it possible to subdivide the space up?

workshop office space, toilet space etc all partitioned off.

 

 

 

It is the plan to do that to an extent. Smaller spaces will of course be easier to heat/insulat.But as its mostly cars involved, theres a limit. And having ramps, there is a resonable height requitrement as well, circa 4.5m min.

[Roger440]

49 minutes ago, joe90 said:

Thermal underwear ?

 

Do that already. The thing is, its an out of control hobby, not a business. If i have to suffer to do it, its no longer enjoyable.

[Roger440]

4 minutes ago, JohnMo said:

And a big jumper.

 

Or heat your body, look at motorcycle and walking body warmers, battery powered.  Then you can what ever temperature you like, for way less effort and expense.

 

Off to google. Didnt know that was a thing.............................

[Roger440]

27 minutes ago, Radian said:

Got 3 Phase? Big Air Con (air to air) isn't all that pricey to buy (£1600 for this 60000 BTU example) Does either heating or cooling.

 

240v only on site

 

Nowhere on that link does it say what the power consumption is. One presumes a lot. My old waste oil burner is 180000btu and struggles to heat it.

[Onoff]

Have you got a big south facing wall? It's an excuse to drink copious cans of beer for a pop can heater! Some of those US sites cover entire house/workshop elevations in them. 

[JohnMo]

1 minute ago, Roger440 said:

 

Off to google. Didnt know that was a thing.............................

I have a jacket for my buggy, keeps you well toastie.

 

There was an article a few years ago, about heat poverty.  This women never heated the house, just wore heated under clothes, for a few pounds a year running costs.

[Roger440]

1 minute ago, Onoff said:

Have you got a big south facing wall? It's an excuse to drink copious cans of beer for a pop can heater! Some of those US sites cover entire house/workshop elevations in them. 

 

Yes, huge. Though in the afternoon, it gets progressively shaded by the trees. The roof less so.

 

I saw you post one of these, but cant find it now

 

Is this really going to work on a british cold wet december?