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43

Good ventilation needs a strategy of its own accord. It doesn't just happen. It will depend on what climate zone you're in, and what your building is, but from your question, I'm going to assume that winter means you're having to use some space-heating to get the home to a decent temperature. The very best ventilation strategy we have, is to make sure that ...


32

Open all windows wide but only for a short period. It will replace the air, but won't cool down the walls. This is the usual recommendation of gas companies.


27

The old farmers' rule of thumb is that you can harvest a cord of wood per acre per year. (For everyone not in the US, a cord is a unit of measure equivalent to 128 cubic feet of tightly stacked firewood, or 3.625 m3. An acre is about 0.4 hectares. So the rule of thumb corresponds to about 9m3/hectare.) (For anyone questioning the validity of this estimate, ...


25

I tend to think renewables (like wood) are a more sustainable heat source than natural gas. There are tradeoffs of course. Most fireplaces are pretty inefficient and can result in a lot of particulates. A wood stove (sometimes mistaken for regular fireplaces) or a pellet stove ensure much more complete burning of the fuel (wood), but require an extra up ...


23

Open fireplaces provide minimal heat to a house, as the warm air heads out the chimney, while cool air is sucked in to the house to replace it. This is a great feature when cooking over wood in the summer, but it's not helpful for staying warm in the winter. You can buy a woodstove insert that will improve the efficiency, keeping more of the heat in your ...


20

Take a look at a passive solar heat collector. They work on the principle of thermosiphoning. The design in the link and the picture below has an additional top vent exposed to the outside so you can close the top interior vent and draw air out of the building during the summer. I've seen more advanced designs that include doors that automatically close at ...


19

General principles The important thing here is to realise what these heaters heat. Radiative heaters radiate infra-red light which strikes objects and heats them directly, heating the intervening air less. Fan heaters primarily heat the air in the room by forced convection. Oil filled radiators, work like ordinary central heating radiators, primarily ...


16

Efficiency The inefficiency you're referring to is probably not the efficiency with which the gas is burned (a separate issue), but instead is likely to be because the air heated by an oven does not mix well with air in the room, so convection causes it to rise straight to the ceiling. This doesn't tend to make a cold house feel much warmer (especially if ...


15

I'll take a slightly different line to Mark Booth's excellent answer. fan heater: If you've got a lot of still air, and / or if you only want the heater on for short bursts, then the fan heater is probably best, because it will get the warm air circulating in the room, and it will respond quickly to being turned on and off. However, dust can settle on the ...


15

There are two main categories to consider here. The first is to improve the efficiency of how your home is kept warm - either by increasing the efficiency of the heating system, or by reducing the rate at which warmth is lost to the outside. If your home is quite "leaky" then major gains can be made this way quite cheaply. Other answers to this and other ...


14

You don't state how much change you are willing to consider. A device called a Heat Recovery Ventilator (HRV) passes the outgoing air and the incoming air through a heat exchanger and transfers the heat from one to the other. It usually would be connected to your central air ducts to distribute the incoming air, and would require pass-throughs for the ...


13

There are various ways to include thermal mass with a lower weight. Different substances have different specific specific heat. So, for a given weight, a material with twice the specific heat, will have twice the thermal mass. Water has one of the highest specific heat values of any known material, so for a heat buffer with high thermal mass, low weight, ...


13

(Corrected)The "thermal mass" value you're interested in increasing is essentially the same (exceptions mentioned in this other answer) as the mass (essentially weight, for those not into learning physics!) of your material multiplied by its "specific heat capacity". That doesn't help much when it comes to keeping mass down. However, there is a way around ...


12

A: Insulate your attic. This can be done in an afternoon. Put 12-16" total in that space. B: Seal the leaks: Weatherstrip the doors and openable windows. All electrical outlets are punctures in the outside wall. You can buy gaskets for them, or you can make them out of the styrofoam meat trays you get from the grocery store. C: Heat shrink ...


11

It's true that all waste heat goes into heating the house, but whether or not waste heat from a lamp or appliance provides efficient and "free" heat depends on what kind of heat source your heat your home with (so turning off the appliance when not in-use or buying a more energy efficient appliance could be better overall). If you have electrical resistance ...


11

No, it is not true if you have a themostat, then there is no such thing as 'waste heat'. If you have a thermostat, there can still be such a thing as waste heat. Space The positioning and timing of heaters around the house typically isn't random: heating devices are typically sited in particular places, facing particular directions, for a good reason: we ...


11

Someone has done it. A majority of the electricity I buy comes from geothermal energy †. Of course, I live in the Pacific Northwest of North America, which puts me close to a tectonic plate boundary. This presents good conditions for extracting geothermal heat (since the earth's crust is thinner at such boundaries ... making shallower wells ...


11

Yes, heavy blankets can be effective insulation over draughty windows; or in open doorways to shut off an unused space: over both, they will hinder heat loss through convection (air currents), and over windows they will add a bit of a conduction barrier too. Castles used to hang tapestries over all the walls, partly to keep some heat it. Ideally, they ...


11

Generally, it makes sense to save power, even during the winter. The difference between space heating and waste heat The main difference between home heating systems and waste heat from electrical appliances is the way the heat is released, and where it's released. Many types of home heating systems are designed to provide heat in a specific way, such as a ...


10

An Igloo is an efficient shelter made of snow/ice blocks. At first thought, the snow is cold so how could it keep one warm. The true value is in the insulation. The design creates a small insulating shelter. The cold weather stays out, the body heat stays in. This is part of the reason they are built small, like tents. The small volume is easier to heat by ...


10

While wood-burning fireplaces have a shorter carbon cycle than coal and gas derived heating and help you to get off-the-grid, they are in no way "clean". The pollution emitted from a domestic fireplace is much worse than the equivalent pollution emitted from dedicated power generation plant for the same amount of heating. The pollution is also local to ...


10

There are drainwater heat recovery systems in production. It is mostly made of copper and in principle it's a passive, opposite flow heat exchanger. The freshwater coming to the house circulates through thin pipes wrapped around a bulky waste-water pipe. Any obstructions in the way of waste-water could cause clogging, that's why there is (probably) only one ...


9

If you have the property, and resources, make sure your house is tight. Then, dig a four foot trench that zigzags across a suitable part of your yard, taking care to call Mis Dig for location of underwater electrical, water, and gas lines. Lay PVC pipe into the trench, making sure it's water tight. Bring one end up from the ground, above the maximum snow ...


9

A fire in a fireplace is pretty to look at but is probably the most inefficient way to heat a home. Not because wood is a poor fuel, which it really isn't, but rather that it is an incredibly poor design for a heating source. A huge amount of the heat goes straight up the chimney. If you really want to use wood as a fuel source the most efficient way to ...


9

First, given that the heat has to go somewhere, I dont think you will get more heat transferred usefully to your house from opening the oven door. You may get less for the reason that the hot air may rise as a mass (rather than trickling out) and thus have less impact on the rest of the air. As some of the others have said the issue efficiency-wise will ...


9

Humidity is a funny thing. The warmer that air gets, the more water it can hold as vapour. When that air cools down, it can no longer hold as much water vapour; if its humidity was high, then some of that water will condense out onto the coldest surface first. So air that has a healthy, comfortable relative humidity of 50%, when cooled, will have a relative ...


9

A related question was asked on SE Skeptics - Is this tealight-flowerpot heater more efficient than just tealights? In the third answer, it is claimed the heat produced by one tea light candle is 0.75 MJ per candle. Where I live, one of the domestic gas suppliers sells gas for 2.78 cents per MJ. The energy value of the gas is 38.713 MJ per cubic metre of ...


8

The absolute most sustainable heat sources are sunlight and waste heat from your body and the appliances you are already using. However, unless you have the resources to build to passivhaus standards, these won't be your primary heat sources in the winter. Geothermal heat systems (not to be confused with ground source heat pumps) also take advantage of ...


8

Your second question is the easy one: it's fine to block off one register, partly or completely. The problem comes when too many of them are blocked off (the furnace can't push enough air to work effectively). If you also have an exit vent in your room a door snake will help keep the warm air from the rest of the house out, once you've partly closed off the ...


8

tl;dr: Yes, lowering the room thermostat at night will generally help save energy, assuming we are in the heating season (winter), rather than the cooling season (summer). Let's take two points in time, one before the night, one after it. Let's choose them so that the dwelling has the same amount of heat energy contained within it at each point, so all the ...


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