What you should know before choosing a heating system. What are the advantages and disadvantages of alternative forms of heating (infrared, electric, solar, geothermal, ions, etc.)? Which is more economical? What effect do they have on health, the environment and economy? Which produce higher levels of electromagnetic radiation?
All heating systems have advantages and disadvantages.
Although for many the main heating systems selection criteria is economic, in our article we will try include other parameters as well and also focus on which heating systems produce more radiation and which have a potential impact on health (which may also cost more in the long run). Generally:
- Systems that create heat using electricity, produce more artificial electromagnetic fields and raise the magnetic fields emitted through the electrical grid (low, medium and high voltage transmission and distribution cables). These systems also pollute the environment since in many countries electricity production is still based on burning coal.
- Systems operating with fossil or "renewable" fuels produce carbon dioxide, microparticles etc. polluting the atmosphere and interior of the house (when there is no adequate ventilation).
- Systems that produce hot air heat the space unevenly, lift dust, need regular maintenance / cleaning of germs and so they create problematic comfort conditions. This is particularly so for people with allergies or respiratory problems.
However, if you make your choice based on your budget:
- In addition to the original acquisition cost, consider the operating and maintenance costs.
- Be cautious when reading various operating cost calculations, as they generally do not take into account the significant differences in the efficiency of each equipment and the actual conditions of use.
- Beware of the return of investment times (ROI) that manufacturers of heating systems give! If you live in a small house and / or do not have great need for heating / cooling then the payback times may be much greater than those advertised.
- Some systems can be used for cooling, so will save you money as you do not have to purchase a separate cooling unit.
- All heating technologies become more efficient and economic over time, while new heating technologies are continuously developed. If you are in no hurry to invest in a new system, waiting some time could mean improved technological solutions with better economic results.
- Keep in mind that the prices of the different fuels, which basically determine the operating costs of each system, are constantly changing depending on conditions and availability. Consider the prospects of each type of fuel in your country long term (eg. are gas supplies in your country high enough to last 5 years or 50 years?).
- The only solution to reduce heating costs, with zero particles, radiation emission and operating costs is the thermal insulation of your home!
Other things to consider:
- How much useful space of your area is occupied by the machinery for each type of heating?
- How easily available and storable the fuel is.
- What are the maintenance and cleaning needs of each piece of heating equipment?
Heating with electricity (electric)
The main types of electric heating technologies are electric radiators, heaters, convectors, heating panels, electric boilers, fan heaters and air conditioners. Their main advantages are:
- There is no need to store fuel.
- The equipment normally occupies little usable space.
- Small equipment maintenance needs.
- Electricity is (almost always) immediately available.
Electric heating and electromagnetic radiation
The switch to heating systems that use electricity has resulted in the population increasingly being exposed to low frequency electromagnetic fields.
Low frequency radiation has been linked to miscarriages, leukemia, breast cancer and skin, insomnia, thrombosis, damage to DNA, diabetes, multiple sclerosis, neurotic disorders, depression etc.
Local high emissions
The area near heating equipment frequently shows elevated levels of low frequency electric/magnetic fields.
Magnetic fields are typically more common in equipment with high wattage, especially in systems using motors (eg. fans) or transformers.
Electric fields are more common when not the heating device is not grounded (has a bipolar plug) or the building has no functional grounding.
Typically the radiation values are reduced to normal levels a meter away from the source, so we recommend that you avoid spending too much time in the immediate vicinity of any heat generating device that operates with electricity (some sources may cause burns within walking distance).
Higher magnetic fields are everywhere
The use of electric heating significantly increases the consumption of electricity, which means that all power cables in the electric grid (low,medium and high voltage lines) will emit much higher magnetic fields especially when there are extreme changes in temperature.
Please note that the electromagnetic fields generated by the power cables today are different from those in the past, not only in quantity but also in quality.
The simple sinusoidal signal of the electric network (50-60Hz) is now distorted by higher harmonic frequencies (thousands of Hz) due to the extensive use of electronic non-linear load devices such as fluorescent lamps, AC adapters, dimmer electronic switches, inverter air conditioners, plasma TVs, photovoltaic systems etc.
This phenomenon is called "Dirty Electricity" because it causes overheating of neutral conductors and premature aging of equipment. Scientists believe that the new wave of power grids is particularly burdensome for humans  .
“Very recently, new research is suggesting that nearly all the human plagues which emerged in the twentieth century, like common acute lymphoblastic leukemia in children, female breast cancer, malignant melanoma and asthma, can be tied to some facet of our use of electricity. There is an urgent need for governments and individuals to take steps to minimize community and personal EMF exposures.” Samuel Milham MD, MPH, Medical epidemiologist in occupational epidemiology. 
In order to figure out if high levels of radiation in your living space are due to your heating equipment, or if it is coming from your neighbours power cables, you can measure it using a simple to use low frequency radiation meter.
Is electric heating "greener"?
Many have the impression that electric heating is ecological because electrical heaters do not operate by burning fuel and produce no carbon dioxide or other dangerous pollutants inside the houses.
However, power plants (which make powering the electric heaters possible) mainly use fossil fuels (lignite) and are responsible for a big percentage of greenhouse gas production in many countries.
For example burning coal to produce electricity produces carbon dioxide, microparticles, and steam which is emitted from the cooling towers of the production units and other pollutants.
Some comparative Greenpeace tables  show that the production of carbon dioxide due to air conditioner heating (electric) is greater than that produced by oil heating.
It is no coincidence that the Nordic european countries have limited the use of electricity as a heating source and have turned to other systems .
Shouldn't we turn to electric heating anyway since fossil fuels will soon will be exhausted?
According to estimates the world oil reserves, natural gas and coal are sufficient to cover our need for 40 years, 70 years and 200 years respectively  .
In addition, the burning of fossil fuels produces numerous harmful pollutants and the fact that most countries import oil and gas from foreign countries means that their prices are volatile and are influenced by many unpredictable political and economic factors.
The future of energy production for many is the generation of electricity from renewable sources (photovoltaic, wind, geothermal, hydro) and the European Union has set a target to cover 20% of energy consumption with renewable sources by 2020.
However, electricity production from renewable sources means greater electromagnetic fields emissions from the power grid with an even more aggravating waveform (with high frequency harmonics) than in the past.
Using renewable sources at a local level would limit the transmission losses considerably and reduce the need for expansion of the electricity network.
Given the large financial requirements of the infrastructure for renewable energy sources and the present economic crisis, some countries should at least temporarily consider other solutions.
Fossil fuels still have many advantages when compared to renewable energy sources, like the fact that they can be stored easily and meet the fluctuations in energy demand.
Some great advantages offered by heating solution that utilize the generated heat from existing thermal power plants (which would otherwise be wasted) are able to carry hot water through insulated pipes to the radiators of an entire city. In this case with only one burner and one boiler located in power plants, an entire city can be heated. This means a lower production of pollutants and zero production of artificial electromagnetic fields. Consumers will also save money by not having to buy a burner, a boiler and other equipment (excluding radiators) while also saving on maintenance costs. This system is implemented in many countries.
Electric radiators, convectors, heating panels
- Contain resistors which are heated
- They are is cheap but have high operating costs
- They are quite and produce heat immediately
- Better for more localized heating rather than for heating the whole house
Halogen, quartz infrared heaters etc.
- In addition to high operating costs they also require special attention to avoid burns and fire.
- Also the light produced can be annoying.
Air fan heaters, air conditioners, fan coils
- The main problem is that they produce hot and dry air that lifts the dust from the floor, creating problematic comfort conditions, particularly for people with allergies or respiratory problems
- They are also noisy and heat spaces unevenly (cold floor - warm roof) and the space quickly cools after shutdown (unlike conventional radiators)
- The inverter technology in air conditioners has reduced power consumption and noise levels compared to conventional, older ac units
- Fan coils in combination with a heat pump offer reduced energy consumption
- Air conditioners need regular maintenance of filters
- Electric boilers contain electrical resistors that heat the water that they contain and which gets transferred to radiators
- They are quiet, have little maintenance and do not occupy much space but have a high operating costs
Electric ion boilers
- These have reduced consumption compared to conventional boilers because they ionize water which makes it heat rapidly
- There are several technical difficulties in their implementation (pipe and radiators corrosion etc.) so it is recommended to use a specialized company for the installation
Underfloor heating with electric resistances
- Underfloor heating systems using electric heating elements instead of water pipes usually create high electromagnetic fields with which we come into direct contact
- The exception is underfloor heating with armored power cables (zero electrical AC fields) and dual core cables (twin-core cables reduces the magnetic AC fields)
Electric storage heaters
- They contain heat resistors which are powered during the night (with reduced electricity prices) and heat the high thermal mass materials they contain (bricks).
- The firebricks transfer the heat to the space in the form of infrared radiation which is considered the healthiest form of heat (similar to the heat of the sun).
- Despite their use during reduced tariffs hours they still consume a lot of energy.
- Also many storage heaters do not heat the area quickly (the area might be warm after some hours).
- The heaters emit electromagnetic radiation fields at night when they are charging so you should avoid placing them closer than a meter from your bed.
Infrared heating panels
- Electric resistors produce long wave infrared radiation which is considered the healthiest form of heat.
- The panels surfaces are coated with special materials (ceramics, carbon polyamide, graphite, quartz crystals, etc.) that absorb the generated heat and radiate it into the living space.
- Infrared radiation directly heats your body and objects without warming the air. Especially objects with high thermal mass (eg. bricks, ceramic tiles), store heat and gradually attach to space.
- Because they do not heat the air but the building materials, it is important to have good wall thermal insulation or else much of the heat stored in the walls and ceiling will be lost quickly to the environment.
- Because they do not heat the air, the feeling you get when you operate them in a cold house is like when you're out on a cold winter day and the sun warms your skin and your clothes but not the air.
- You must also have visual contact with the panel for it to warm your body. For this reason, many prefer to use infrared panels for spot heating, not for heating the entire house.
- Compared to oil or gas heating, infrared panels have lower purchase costs and do not occupy much usable space.
- They have reduced consumption compared to the most electrical heaters.
- They help to reduce the humidity in the walls.
- They are simple to install and require no maintenance.
Are infrared panels safe? Don't they emit dangerous ionizing radiation?
Infrared radiation is equivalent to the heat from the sun, fire and the heat produced by the human body.
It is close to the spectrum of ionizing radiation, with slightly lower frequency than UV radiation and natural sunlight.
However, even ionizing radiation (which exists since the dawn of man) in specific amount has a beneficial effect on the human body (e.g., UV radiation helps to produce vitamin D hormones, radioactive baths around the world are used for therapeutic purposes). Read more in our article on ionizing radiation..
Infrared radiation is believed to help improve blood circulation, also in arthritic and muscle problems, detoxification etc. and is used in incubators for premature babies.
In our opinion the modern man who spends small amount of time in nature and the sun may have greater need for the beneficial properties of infrared radiation.
An important advantage of infrared panels is that they do not create unhealthy air currents carrying dust and microorganisms in the living space (as air conditioners do) and help to reduce moisture and mold growth.
There is research  claiming that acute and chronic exposure to ultraviolet radiation could cause eye damage. For this we suggest that you avoid prolonged exposure to direct visual contact with the panel (better to view the panel from the side or rear), especially in the case of cheap infrared halogen heaters that produce light which is also annoying for the eyes.
High temperature panels (~ 300 °C) must be placed in a high space in order to avoid burns or other accidents.
Infrared panels also emit low frequency electromagnetic fields that are not considered biologically friendly to humans. Our measurements with infrared panels showed elevated magnetic fields at a distance of <1 meter from the panels.
Alternative infrared heating systems such as storage heaters (charged and then unplugged) and high thermal mass fireplaces which produce wholesome natural infrared radiation without artificial radiation.
Heating with combustion
Burning oil, gas, wood, pellets, etc. for thermal energy produces carbon dioxide capture, micro particles and other pollutants that contribute to air pollution and global warming.
The effects of induced air pollution are greater when combustion takes place indoors with poor ventilation.
Oil burners - boilers
Oil is burned in the burner and the boiler heats water which flows through pipes and is transferred to radiators.
- Oil is readily available in most countries.
- No radiation emissions.
- High purchase costs (burner, boiler, piping, radiators etc.)
- Occupies a lot of usable space
- High operating costs
- High and constantly changing fuel costs
- Needs maintenance
- Oil is not a renewable energy source
- Needs supply through tankers
How to reduce your operating costs
- Regular boiler burner maintenance (at least annual)
- Repair defective piping insulation
- Replacing old boilers which have low efficiency (30-40%) with new, more energy-efficient systems that operate with an efficiency of> 80% (eg. condensing boilers or high efficiency boilers that recover the lost thermal energy from the combustion of fuel)
Gas burners - boilers
Natural gas compared with oil:
- Is usually cheaper
- Is continuously available and does not need to be pre-stored
- Typically uses newer generation boilers with better performance
- It has a faster response to temperature setting
- need a developed distribution network that brings gas to your neighborhood
- Monthly fee for gas supply
- High purchase costs (burner, boiler, piping, radiators)
- High operating costs
- Constantly changing fuel costs
- Needs maintenance
- Natural gas is not a renewable energy source
Biomass burner boilers (wood, pellets, etc.)
Biomass materials are materials of organic origin like wood, pellets (compressed pieces of various plant products, sawdust, etc.), bioethanol (alcohol produced from plants such as sugar beet and corn) etc.
- Biomass is considered a renewable energy source because whatever is cut down can be replanted
- There is possibility of domestic production
- Lower cost consumption compared to oil and natural gas (depending on the efficiency of the boiler and fuel)
- Relatively small operating costs
- Takes up a lot of useable space (burner-boiler + storage)
- High maintenance when using low quality wood or pellets
- Continuous feedback needed (depending on the type of biomass and the burner)
- Regular cleaning
Is biomass really an ecological energy source?
Biomass is considered not to be a contributing factor in the increased carbon dioxide in the atmosphere (CO2 neutral) because the carbon dioxide produced had already been removed from the atmosphere during the growth of the tree or plant from which it originated. This is especially true since a new tree or plant will be planted in place of the one that has been cut down.
But is this really what happens? Alex Scrivener policy officer at the World Development Movement, claims that  :
“Substituting biomass for fossil fuels sounds like the easy solution to climate change. But in reality, it leads to land grabs, the destruction of rainforests, and severe food shortages where land is used to grow fuel instead of food. And the idea that biofuels are ‘carbon neutral’ is a myth."
In reality, biomass is mainly imported from third world countries (imported CO2 without local replenishment) where large areas are often never replanted.
Even if replanted, the new trees take years to replenish the lost oxygen.
The use of biomass as fuel also leads to the rise of illegal logging and monoculture for biofuels (which may have an impact on local biodiversity and soil).
However our opinion is that biomass can be a good alternative to fossil fuels, provided the production is controlled and permitted only when the necessary conditions are met.
Fireplaces and stoves, biomass (wood, pellets, vioaiathanolis)
- Biomass is considered a renewable energy source if replanted after cut.
- There is a possibility of domestic production
- Lower cost than oil and natural gas
- Aesthetically beautiful
- It is necessary to have ventilation and also a supply of fresh air
- The existence of a burner inside the house is dangerous
- Temperature control weakness
- Regular and difficult maintenance
- Continuous need to feed the fire
- Various weather conditions (high outside temperature, windy, etc.) can make the removal of the combustion gases difficult (chimney smoking)
- Storage need
Oil stoves, kerosene, gas, wood, pellets etc.
- Used mainly for spot heating
- They are usually a cheap option but their quality varies considerably from model to model
- Exhaust ventilation necessary
- Beware of leakage in gas stoves
They are open and not recommended because:
- They have very poor yield 10-30% and consume a lot of fuel
- They produce many pollutants
- They consume a lot of oxygen meaning you must have an open window
- They need constant supervision
Energy efficient - thermodynamic fireplaces / stoves
- Fireplaces generally have doors with with fireproof glass. Thus, the wood burns with less air and the degree of efficiency reaches 70-75%.
- They need less fuel and reduce the pollutants and air loss from the house.
- They do not need constant supervision.
- In thermodynamic or ecological fireplaces an additional mechanism that reburns the exhausted gases further increases the efficiency of the fireplace and minimizes pollutants.
- They may have vents at the bottom, were cold air enters and is then heated (through airways - not in contact with the exhaust gases of the outbreak) and comes heated out of the top vent.
- By using fans and air ducts you can also warm other rooms.This duct system inside the houses is not recommended because it produces hot and dry air that lifts the dust, creating problematic comfort conditions, particularly for people with allergies or respiratory problems. It is also difficult to purify the airways from dust and germs.
- However, if you choose to have hot air coming from the fireplace, choose a fireplace in which the air is drawn from outside (fresh air) and not from inside the house.
- A better solution is to connect the fireplace to radiators through water pipes.
- The fireplaces that burn bioethanol (fluid) do not make smoke and only emit small amounts of carbon dioxide meaning they are usually open-ended and do not work with chimney
- Low selling price compared to other fireplaces and are aesthetically very beautiful
High thermal mass fireplaces
- High thermal mass fireplaces (masonry heaters) are built with ceramic materials, bricks, marble and other high heat capacity materials
- The combustion takes place with a closed hearth and with a small amount of fuel, as a result minimal exhaust gases are produced from the chimney
- The hot air which is generated heats the bricks which store the heat and emit it in the form of healthy infrared heat for several hours after the fire goes out
- Usually the large thermal mass fireplaces occupy a large area and are placed in the center of the room
- Their problem is that after you start the fire it takes a while for the room to get warm
- Also, after you turn the fire off it takes a while for the room to get to normal-low temperatures
- It is in our opinion one of the most hygienic ways of heating that has existed since ancient times (Roman hypocaust) and is very popular in the Nordic countries
Heating with heat pumps
Heat pumps may be the most cost effective heating systems since they produce heat which they derive from the environment with a relatively small use of electrical power (depending on conditions).
They save space (no boiler and fuel storage), do not generate combustion pollutants in housing and can also be used for cooling.
What determines how economical their function is, is their coefficient of performance (C.O.P.), which is usually high (3-6). For example C.O.P. 5 means that for every kilowatt of electricity consumed, they produce five times the amount of thermal energy.
The smaller the temperature difference between the heat pump source (air, water, earth) and the heat medium of the terminal units (for example, water in radiators), the less the electricity needs to be consumed.
Therefore, heat pumps are ideal in combination with low temperature systems (eg. radiators with large panel-type surface or floor heating or fan coils). Low temperature systems (30-40 degrees) require less energy to heat the room in relation to traditional radiators panels (70-80 degrees).
- The most common heat pumps are pumps that use outside air. They are an economical type of pump, however their performance drops significantly and their power consumption increases when there is a large temperature difference with the air outside.
- This means that the air heat pumps are consuming a lot of power during low outside temperatures, or when you adjust the thermostat to reach high temperatures inside.
- Also the outdoor units of air pumps occupy space outside and are aesthetically unpleasing and are vulnerable to theft.
- The air-to-air pumps produce hot air via fan coils or airways. Air-to-air pumps are air conditioners. The inverter type of pumps have a more economical operation.
- Like all corresponding systems that heat the air, they are not considered healthy because they produce hot and dry air that lifts the dust from the floor, creating problematic comfort conditions, particularly for people with allergies or respiratory problems.
- They are also noisy, heat the space unevenly and require regular maintenance of the filter.
- We recommend to look for systems that also offer moisture regulation as well as the supply of fresh air in the room.
- The air-water pumps heat water. If you have traditional radiator panels you will need a high-temperature heat pump. If you have large radiator panels or floor heating you will need a low-temperature heat pump (most economical operating costs).
- The pumps with the highest degree of performance and the least operating cost are geothermal pumps. These harness the heat in the ground several meters below the surface of the earth or the heat of groundwater (underground temperature shows small variations in contrast with the outside air)
- The disadvantages of geothermal pumps is the high cost of installation and the need for installation space and 40-100 sq.m. for drilling
The ideal choice in our opinion for new homes is the combination of a geothermal heat pump with underfloor heating and undefloor or ceiling cooling. Additionaly there is a combination with a photovoltaic system through which you can annihilate operating costs for heating. A system of water pipes in the floor:
- Creates optimal conditions of thermal comfort in relation to all systems and evenly distributes the heat to the space.
- Does not occupy useful space inside the house and gives you freedom in the layout of the house.
- Operates silently.
- Works even more economically when the floor has large thermal capacity ceramic tiles (as opposed to the wooden floor).
- Does not lose heat quickly after you turn it off.
- Takes long to heat the room after it becomes operational (unsuitable for vacation homes).
- If there is damage the is repair difficult (although installation companies give many years of guarantee and damage is rare).
- It is the ideal system for cooling a space.
Heat from the sun
- Solar heating systems function similarly to water heaters, however, require much larger collector area.
- The water is heated by solar panels used on radiators.
- They have a high installation cost.
- They operate economically when there is good thermal insulation and low temperature radiators present (large-area radiator type panels or underfloor heating).
- The system is problematic on days when there is not enough sunshine, so an auxiliary boiler may also be necessary.
Insulation: The best solution to reduce heating costs
The inner or outer insulation of a building is the most reliable and ecological solution to reduce heating costs.
It restricts the entry of cold air into the house and also reduces the heat lost to the environment.
In a building with no thermoregulation you can achieve a reduction of up to 50% when it comes to heating and cooling costs.
Basic insulation solutions are:
- Thermal insulation of external walls and roof : This is done internally or externally with materials such as glass wool, cork, rockwool, polyurethane, perlite etc.
- Double glazing or thermally insulated windows : In this case do not forget to ventilate your room regularly during the day.
- Thermal insulation of pipes and radiators : The insulation of pipelines going outdoors or spaces not required for heating is necessary. Also use reflectors (eg. aluminum) for radiators in contact with the outer wall.
Alternative proposals for reducing heating costs
- Dress warmer.
- It is not necessary to dress in a t-shirts at home even during the coldest winter days! Try to dress warmer before turning on any heat source.
- Use a thermostat.
- Use thermostats (where feasible) to avoid unnecessary operation of heat sources. Set the thermostat at normal temperatures (20 to 22 day and 16 to 18 hours). Don't ask for 25 degrees when the outside temperature is 5 degrees!.
- Take advantage of the sun's heat.
- If your house has an opening to the south (for the northern hemisphere - the opposite for the southern hemisphere), leave it open during the day so that abundant infrared heat enters from the sun. Especially if you have floors with high heat capacity (eg ceramic tiles) this heat will be stored and transmitted after dark.
- Other passive solar systems that are more easily incorporated into new homes may also be an option, such as solar patios (indoor spas with windows in the roof) and solar walls (glazing on the outside the walls which functions like a greenhousess, accumulating heat from the sun and transferring it inside the building). In such cases it is advisable to have the possibility of selective shading so that there is no unwanted increase in temperature during the summer months.
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