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I am about to buy a flat that hasn't got any central heating system. There's no way to use gas heating.
The only way to produce heat is by converting Electricity.
The flat at the moment has some electrical panels mounted close to the windows, but I don't see it as an efficient solution.
I am considering heated floors, but I am interested in hearing from you. I want to use the heating method that is energy efficient / calorific power balance.
100% of electricity is converted to energy is true. But what is the energy used for? Generate heat, as in resistive heating? All of the electricity is converted to heat, sounds efficient. But you can do better. You can use your electric energy to move heat obtained for free from somewhere else. In other words, a heat pump is more efficient than resistive heat. The source of free heat can be the air, the ground, or even ground water. How the heat that is moved into your house is distributed can vary. You can blow heated air around, or you can move heated fluid around. The heated fluid can give up its heat at radiators, or base board heaters, or into your floor.
There's many options, but you should get heat by moving it rather than causing resistive wires to give it up.
All electric heaters are 100% efficient, converting all consumed electrical energy into heat.
These types of heaters consist of a heating element, and a reflector. They are used to heat objects, rather than the air in a room.
These types of heaters are useful when you only need to heat a small area of a larger room. They are typically used in garages, and other similar buildings where heating the entire building is not a requirement.
These types of heaters consist of a heating element, and a fan. They work by forcing air across the heating element, warming the air and circulating it into the room.
They are best used in smaller spaces, where quick heating is required.
These types of heater contain a heating element that is open to air flow (some include fans to increase air flow), allowing them to warm and circulate the air using convection.
These are good for medium sized rooms, where longer periods of heating are required. They may take longer to heat a room, but produce a steadier more even heat.
These types of heaters use bricks (or other materials) to store heat during "off-peak" hours, and then release the heat during "peak" hours.
They can be useful if most of your heating demand is during "peak" hours (assuming your electric company has off-peak rates), but are not so good if most of your demand is during "peak" hours.
These are typically various size mats, which are installed under flooring. They can be useful to heat large rooms, but can be expensive to run (since they have to transfer heat through various floor coverings).
With these type of heaters it is very important that the underside of the floor is well insulated, to prevent heat from transferring down instead of up.
While some people like to compare heat pumps to electric heaters, they really should not be lumped in with electric heaters. Yes, they use electricity, but they do not use electricity as the primary heat source. Heat pumps work by circulating coolant through plumbing to draw heat from the environment, and then release it in the home.
Because heat pumps extract heat from other sources, they can be greater then 100% efficient. Some heat pumps use an electric heating element as a supplemental heat source, when environmental heat is not sufficient.
If you have the ability to do so, installing a heat pump may be your best option. The initial cost of installation may be quite high, but the operating cost savings may compensate for this. You'll want to calculate your ROI (return on investment), to determine if this is an economically viable option.
Purely electric resistive heating generally provides you with 1 Joule of heat for 1 Joule of energy, regardless of outdoor temperature.
However, a heat pump can provide you with ~ 2-4 (or more) Joules of heat for 1 Joule of energy . Whether you get 2 or more Joules depends on the outdoor temperature. The lower the outdoor temperature, the fewer Joules of heat you get per Joule of electricity.
As the outdoor temperature approaches -12 degrees Celsius (depending on model), the heat pump becomes less efficient (and probably less effective) and you need to switch to (or add) an auxiliary heat source like electric resistive heating.
A heated floor is good since it makes you 'feel' warmer. If you're renovating, be sure to insulate to keep the heat in which will keep you more comfortable and lower the energy bills whichever way you go.
So the best would be to have a combination of both, assuming the climate you're in goes down anywhere near -12 Celsius.
The heat pump will also provide cooling (air-conditioning) during warm weather.
In Canada, we size heat pumps for ~ 100 - 120% of the cooling load, and then supplement the heating with auxiliary systems.
There are also split-type heat pumps, since, I assume you don't have a central air system.
Electric heat is 100% efficient, but the kind and placement of the heaters affect how the heat it distributed in the room, so with appropriate choices you can be comfortable with less heat.
Wall-mounted panel heaters are often mounted under the windows because the windows are typically the greatest point of heat loss in a room. Without a heat source near the windows, these parts of the room will feel cold, and you will want to turn up the thermostat. (This is not specific to electric heat: radiators are typically placed under windows, and forced-air vents are typically above the windows. This placement also has the benefit of typically not being in the way of any furniture.)
Another good choice is radiant floor heating, as cold floors make you feel cold and turn up the thermostat.
Electric Resistive Heat is only 35% efficient. In terms of electrical usage. When the element is cold, it draws a lot of current (that which is recorded on the metering device) (aka surge current) As the large current draw continues, it heats the element until it becomes more resistive requiring less current. Once it has become more resistive, the current creates the heat you feel. This continues until either the element burns out, or the high set point of the safety switch turns off the power. When the low set point temp is reached, it is less resistive and takes more current to build up the resistance to create heat once again. All Heat is used, so in that sense it is 100% efficient, however it is not an efficient use of electricity or your money.
43 years in the Electrical trade is my source of research.
A heat pump is cold because the temp that it produces is colder than other heats even if the heat pump heat is a warm temp. A heat pump is pretty much a cooler in the north but is great for the south. Coal heat is the best one can chase everybody out of the house in the dead of winter with coal but we all know about coal. Oil heat to much maintenance. Gas used to be less expensive. Short of burning wood that you got for free but put alot of labor in to get it we pay. Electric heat whew who priced that. Insulate insulate insulate seal the cracks buy good windows. Change the furnace filters and clean the cooling coils. Heating elements can run you broke say you have your electric furnace going your dryer running your hot water tank heating water and you are makeing toast that will send your electric meter in to outer space that it is spinning so fast. Tubes of caulking are inexpensive seal up those cracks and there are many publications on other things to do. Take it from a man who paid a 1,130.00 dollar electric bill this winter for one month. And yes I worked in the HVAC industry for over 30 years there are things you can do to safe a buck.
