Is it better to choose a pellet boiler, a heat pump or even wait for hydrogen fuel cell technology? There are many questions you can ask yourself and the answers all depend on the same starting point: it all depends on the insulation of your building or home. Here is our advice when it comes to picking the right heating system with the right technology for your house.
As everyone should know, the first step in answering the question of heat production and energy efficiency in a home is to run an energy audit by a certified professional plumber or hot water specialist auditor.
This expense often seems superfluous, but it is essential in order to objectively identify possible solutions and to be certain that financial savings will be made.
On the basis of the results of this energy audit, a final heat requirement for home heating and hot water will be determined, possibly after carrying out work to reduce these requirements to a greater or lesser extent.
Here are our tips on the options available to you.
If your home is poorly insulated and consumes a lot of energy
If your home is poorly insulated, your heating needs will be high.
This means that you will need to produce a lot of heat during many months of the year. Strategically, it makes sense to opt for systems that combine heat and hot water production in the same system.
This is because the need for domestic hot water will be quite small compared to the need for heating, and this domestic hot water will therefore be produced alongside the need for heating.
In these cases, the interesting renewable solutions are :
- A pellet boiler connected to a network of radiators and the domestic hot water boiler. In addition, you can install thermal or photovoltaic solar energy to produce hot water (during the 3 to 4 months when the boiler is off).
- A wood-burning stove is also possible, allowing you to keep your boiler off during the summer, but this is more of an amenity than a real saving (energy or financial).
On the other hand, here is what is not recommended, because the needs are too great and the final bill would be higher (whatever the salesmen say):
- Geothermal heat pumps, (which get heat from the ground), as they will consume a lot of electricity, which is more expensive than gas.
- Aerothermal heat pumps, (which seeks heat from the air), for the same reasons as geothermal heat pumps and because their performance is less good than that of geothermal heat pumps.
- Connection to a heat network, which conveys a temperature that is too low to ensure comfort.
If your home is more energy efficient
As the performance of your home improves (and therefore its heating needs decrease), you may consider a new strategy (unless you are connected to a common heating network):
You will have hot water needs all year round, while the number of months without heating needs increases with performance.
It, therefore, becomes interesting to consider the production of heating and domestic hot water by more or less separate elements.
– For your hot water needs
In these cases, it is interesting to produce domestic hot water with :
- A photovoltaic hot water solar system combined with a conventional electric boiler. The consumption of the DHW tank resistance (+/-2,500 kWh) will be partly compensated by solar production. The solar coverage can be up to 80% with proper sizing and sun exposure.
- A photovoltaic hot water solar system combined with a heat pump. According to this website, your system should consume 2 to 3 times less electricity and it will also be mostly renewable energy. It is more expensive to purchase than the previous solution, but the photovoltaic installation can be smaller for the amount of same solar coverage.
- A solar thermal system. This is the most expensive solution (and the one that works less often during the year). Even with a larger collector surface, solar coverage is often around 40-65% over the year.
– For regular home heating
Solutions are becoming more diverse:
- Wood pellets are recommended for small boilers or even stoves connected to a few radiators or floor heating.
- Pumps connected to photovoltaic solar energy will be very efficient (and therefore inexpensive to use), but often relatively expensive to install.
- Heat pumps are cheaper, but will be reserved for the most efficient houses because in very cold weather their performance is relatively low (and therefore expensive to run).
If your home is very energy efficient and well insulated
If the energy performance of your home is really high, the heating needs are limited to a few days per year. The heat requirement for heating can then be met by electric heating (although this is not recommended in non-passive buildings). Indeed, these quantities will be quite small compared to the additional costs of installing a heating distribution system for such buildings.
What about hydrogen fuel cell technology?
This solution, which can be placed in the micro cogeneration class (not yet mature, either technically or economically for residential use), should be considered in the same way as heat pumps.
It does not change the need for heat (which remains to be minimised) and is highly dependent on the cost of electricity production, which is necessary to manufacture hydrogen.
These are solutions to be followed closely, but their development does not suggest that they will be used for residential purposes in the next 10 years.
In addition, many actors in the energy transition are opposed to the use of hydrogen to heat buildings because it is less efficient and more expensive than heat pumps.