electric heating

I don't think so. At 5C, they're already running resistive (Aux) heat.

But I do know it depends on depth. But you specified 18 inches. And my ref. clearly shows this. It may not be easily interpreted by you, but others are more capable.

Explain how I am dim. You are the one that said six month lag. I just pointed out that the lag at 18 inches is about one month. No where near six months that you stated.

A typical Sloman reply to a past showing him posts are incorrect.

Sloman is a fraud.

Dan

but molten it does have a rather violent reaction with water

-Lasse

On Tue, 17 May 2016 17:02:08 -0700 (PDT), snipped-for-privacy@ieee.org Gave us:

And if you looked at them you would have noticed where they said that "liquid Sodium" IS one such 'salt'.

Ahh, no. It's (the ideal efficiency) just a ratio of temperatures, T_hot/(T_hot-T_cold) in absolute units* (K) (it might be T_cold on top.) In practice you get less than that.. but a man's gotta know his limitations! :^)

George H.

• 300 K from 270 K is ideally ~10:1, 1000% efficiency..

Sodium, liquid or otherwise, is *not* a salt, AlwaysWrong.

But not the nature of the surface. I may have remembered the depth wrong, but it's not impossible that eighteen inches may be enough to give a six months lag for a particular situation.

You seem to have grabbed the first link that Google gave you - based on the fact that it was the first link that it gave me.

If you dig deeply enough into the document to which you posted a link, it does make the point, but you should have extended your search (to the next item on the list) to find something that made the point faster and more clearly

We aren't posting stuff here to prove that we are right, but rather to get the basic ideas across as quickly and easily as possible.

See above.

For a particular - unspecified - situation. You don't know what kind of surface I was talking about - and neither do I (now). The 45cm stuck in my memory, but not the exact situation being talked about.

For a particular soil type.

Not true. Dan is dim, and can't really get his head around the idea that the world is a little more complicated than his mental models take into account.

Perhaps, but filling an unspecified volume with an explosive mixture of hydrogen and air and having that ignite can create quite extensive destruction.

Search on fuel-air bombs and Flixborough (where the fuel wasn't hydrogen, but the disaster managed to create an explosive cloud with something where it isn't quite as easy as it is with hydrogen, though cyclohexane is pretty flammable).

Sodium is an element, not a salt.

Bill Sloman, Ph.D. (Chem), Sydney

In theory, theory and reality are the same. In reality, any match between reality and theory is purely coincidental.

In reality, heat pumps don't work much below 0C. Mine demonstrate this simple principle every Winter (the Aux heat comes on at 40F).

Not if you have a good grasp of the theory.

Theories are always applied to a simplified model of reality. Anybody with an sense - and krw doesn't seem to have any sense at all - allows for the implications of that simplification.

Far from it. Theories get chucked out if they don't come out matching reality pretty closely, and get replaced by new theories that do better - ellipses versus epicycles.

Heat pumps have to work harder when the temperature difference they are asked to bridge gets larger, and when they are being asked to deliver more heat at the same time they do run out of capacity.

You can design a heat-pump based system that will keep on delivering enough heat, even in the depths of winter. It would be ridiculously over-sized during the rest of the year, and in practice the extra capital cost is impossible to justify.

Paying through the nose for direct electric heating for a few very cold days in winter turns out to cost less than the through the year interest on the kind of loan that would buy a heat-pump big enough to deliver enough heat on those very cold days.

In California and Texas (how's that for contrast?), plus perhaps Utah if it isn't killed in committee, new gas-fired water heaters are required to include Ultra-Low-Emission technology, with a modified burner that reduces NOx emissions.

On top of that, the new Federal efficiency requirements for water heaters (gas or electric) result in a bigger size that may not fit in some existing WH locations.

Like our high efficiency, no-phosphates dishwashers. We pre-wash the dishes with lots of hot water, then we run them in the the dishwasher once or twice.

Our low-flow toilets have to be flushed several times per, well, major event.

On Tue, 17 May 2016 23:26:21 -0700 (PDT), snipped-for-privacy@ieee.org Gave us:

So is what they are using in the systems in question. Even those called "liquid Sodium" are using a salt of Sodium. Maybe you should be telling them.

As long as you don't have to turn on the outdoor heater to prevent the thing from icing up, which of course is the fly in the ointment.

Cheers

Phil Hobbs

I took thermodynamics a long time ago, and wasn't terribly interested

I just use sodium tripolyphosphate from eBay. Works great, and isn't going to eutrophy the Hudson estuary any time soon.

So does one of my 5-gallon American Standard ones, circa 1960. The bowl is too nearly circular in outline, so stuff tends to orbit. The 1.5 gallon one here at the lab (circa 1980) is much better.

Cheers

Phil Hobbs

Liquid sodium is the molten form of the metal - still an element. Molten sodium and potassium nitrates - which are what mostly seems to be used - are salts.

You don't need much in the way of chemical education to know that.

ce over which it has to be transferred increases, but if you are using a he at pump for heating, the waste heat from the pump should be warming your ho use or whatever.

ysics to apply the math to, which you seem to have skipped.

reasonable house" is super-insulated. There's a whole community out there t hat fills special interest magazines with endless articles on the subject.

be on top of the hot water tank, so it's stealing heat from your home hea ting.

utside the house.

g at a constant temperature difference, the thermodynamics aren't quite as favourable as they claim.

Yeah- they're junk in the heating season and somewhat helpful during coolin g season. As for geothermal, they work great year round and at high efficiency. The o ne I have uses direct ground to refrigerant exchange, there is no intermedi ate efficiency killing glycol loop. The ground heat exchangers are simple s ingle loops of copper pipe (200x the conductivity of polyethylene), one loo p per 1/2 ton capacity, loops connect into manifold, manifold to single pip e to ordinary mass market scroll compressor. The loops are inserted into sm all boreholes to a 60 ft. depth separated with a 60o offset from horizontal making for a compact installation. The copper piping is protected with a c ontinuously brazed sacrificial electrode wire along its axis making for an effective lifetime well in excess of anything considered satisactory. Since the heat transfer is between thermal sinks effectively at constant tempera ture year round and day and night, a characteristic critical to the mechani cal pump technology, efficiency is very high.

ence over which it has to be transferred increases, but if you are using a heat pump for heating, the waste heat from the pump should be warming your house or whatever.

physics to apply the math to, which you seem to have skipped.

"reasonable house" is super-insulated. There's a whole community out there that fills special interest magazines with endless articles on the subject .

to be on top of the hot water tank, so it's stealing heat from your home h eating.

outside the house.

ing at a constant temperature difference, the thermodynamics aren't quite a s favourable as they claim.

ing season.

one I have uses direct ground to refrigerant exchange, there is no interme diate efficiency killing glycol loop. The ground heat exchangers are simple single loops of copper pipe (200x the conductivity of polyethylene), one l oop per 1/2 ton capacity, loops connect into manifold, manifold to single p ipe to ordinary mass market scroll compressor. The loops are inserted into small boreholes to a 60 ft. depth separated with a 60o offset from horizont al making for a compact installation. The copper piping is protected with a continuously brazed sacrificial electrode wire along its axis making for a n effective lifetime well in excess of anything considered satisactory. Sin ce the heat transfer is between thermal sinks effectively at constant tempe rature year round and day and night, a characteristic critical to the mecha nical pump technology, efficiency is very high.

Fred, what's on the other end of your heat pump? Do you circulate warm air or warm water?

George H.