Induction Heating

What are you going to heat by induction?

Two cup of tea.

If you cant afford to heat two cups of tea you cant afford an induction heater either!

How do you plan to heat the tea using an induction heater anyway? Induction is electromagnetic and only works on moderately conductive materials like metals.

Nowadays there are much more efficient ways to build a house.

We NEVER use a heat source in the house. In the coldest days we just let the sun heat up our interior - furniture - walls - and thick concrete floor that sits over a 4 feet high basement.

All walls are styrofoam boxes, poured with concrete.

The insulation factor of our house is 2 X better than a modern refrigerator.

Avg. 1/4 plaster + fiberglass net + 2,5 inch styro + 7,5 inch concrete + 2,5 inch styro + 5/8 gypsum board.

Trocal PVC doors and windows have rubber gaskets and 5 point locks - triple glaze.

In winter we play a little with blinds and have a comfortable temperature.

In summer we exhaust the hotter air just below the 10 feet ceilings and manage to use AC for less than a month and 9000 Btu's per 1100 square feet to get the temp

to 25 degrees celsius.

Climate like South Florida.

I hope to bring also good news soon on how it works with $0.00 power bills on 2500 Watts solar panels for a total of 8,000 Square Feet living areas.

(for 3 families)

Avg. 1/4 plaster + fiberglass net + 2,5 inch styro + 7,5 inch concrete + 2,5 inch styro + 5/8 gypsum board.

That is more than 13 inch wall !
Wonder how much more it will cost to have this elaborate wall construction.
Also, what about your roof , you must have equally well insulated roof, how is its construction like?
Hope you can share your experience.

bravo88,

What he has described is like a standard 8" ICF (insulated concrete form) wall with a standard synthetic stucco exterior and directly-applied fire rock on the inside. The typical installed wall cost is about 10-25% more than for a stick-built 2x6 frame wall, but much less, if you did your stick-built to the same energy efficiency numbers. In a temperate environment, the annualized R-value for the wall is close to R-50 (but the ASHRAE value is closer to R-26); the air infiltration is zero, the risk of mold or mildew is virtually zero, and the strength is beyond compare (try wind speed resistance greater than 200mph).

At the top of the wall, use trusses with a high-heel (minimum 12") and Simpson or equal strap ties that are embedded into the concrete when it is poured. These ties will wrap around the truss and can give uplift strength well above the uplift of a 150mph wind for very little cost increase over the uplift strength needed for a 115mph wind. This roof construction will allow blown-in R-50 cellulose insulation. If you want a sloping ceiling (aka cathedral ceiling), you can opt for thick factory-built panels sandwiching polystyrene foam between two layers of treated OSB, and get a similar R-value and fairly-fast erection.

These construction methods are readily available in all areas of North America as well as over 50 countries world-wide. They are recognized within the International Residential Code as well as a number of other model building codes.

--John M.

Only the block is a typical 11" wide ICF. You can find the specs under I.C.E. (isolated concrete efficiency) block. Was one of the first serious ones but probably also the most expensive, compared with what is offered now.

These have metal sheet bridges inside. You can have a look at what the concrete at the inside looks, when you see the wall of the garden. Here the styrofoam has been stripped off afterward to have the pattern showing. The structural concrete has a wafer wall frame with 8" concrete columns (1 rebar #5) inside and horizontal connection beams with the same rebar. We have build 3 buildings: the shown one is designed and tested in the mean time for wind speeds up to 380 Mph. The shutter system 350 Mph.

The house has been in 1 hurricane #5 and been struck by a tornado in it for now. The owner considers calling it tornado home now.

The stucco is applied on a synthetic mortar bed that has fiberglass mats in it.

The other building are much higher and bigger: resp. 18,000 and 45,000 square feet with the equivalent of 4 storeys. Apart from roof tiles there has been no substantial damage with none of them.

ICF manufacturers are too optimistic when it comes to time consumption to use it. We paid the block like $15,00 for the equivalent of 6 regular building blocks. Add steel and concrete here and your wall costs more than double. However the payback time is fast.

People with similar square feet houses pay a power bill of $2,000.00 here while this one here is only $250.00.

Induction heating of water is less economical than resistive heating, which is close to 100% efficient:

http://cr4.globalspec.com/thread/23389/Magnetic-induction-for-hot-water-heaters

In the case of an electric radiator, you are also bound to lose efficiency by using induction instead of directly generating heat by passing current through resistors in series. And it will cost more to build it, to boot.

I got curious and had a look to see if there's a workable microwave heating design, and that doesn't look promising either. The commercial prototype that was hyped in 2005 turned out to be 'vaporware'.

The heat pump is the only technology that offers more return for the input than resistive heating - by using energy to scavenge heat instead of making it.

You can only effectively "induction heat" paramagnetic materials like (some, not all) metals. The only gain you can pursue with induction heating is the energy difference for the less mass that has to go to final temp, mass that normally includes the heater itself, surrounding structure etc. But you do add significant conversion losses, so it's only worth the trouble in certain cases like very high target temperatures e.g. metal furnaces (that a resistive element wouldn't handle) and/or very low duty cycle (that would make heat insulation for your device impractical) and unfavorable mass ratio between heater (and it's structure) and the item to be heated. (e.g. a cooking pot) S.M.

GA for you.

Why not heat water etc in well-insulated containers. Most are thin plastic or metal.

Also for cooking use an electric frypan with a lid, sitting in an insulated bed, and an insulating lid over it. With a large frypan, you can bake in this instead of using a badly insulated oven. The oven could be insulated on the ouyside with glasswool batts.

You could also use an open fire or hot rocks.

Forgetting for the moment induction cooking (with the right pots and pans of course, the ONLY way to cook on a stove!) as that doesn't belong here!

I personally cannot imagine how any form of induction can be used to profitably heat a house or apartment......but of course I am not some "fly-by-night" salesman, I am sure that some of them have completely opposite ideas.......

Firstly, as mentioned already, electric heating is not the best (financially) way to go. If you have no other choice then use resistive block heating with louvres that you can adjust to change the temperature, with "over-night" (usual in many parts of Europe) heating on a cheaper tariff than normal......

A well insulated house will repay its cost many fold with regard to the electricity bill!!!! (also as several have already mentioned!!).

The best way is always to reduce your reliance on any fossil fuel, or energy source that uses fossil fuel....be CO2 aware as well......

Best of luck........

Is this what you want to use to heat your home?

You may need the Chinese to hook it up for you.