A common question is which energy source is best for heating buildings. By “best,” we mean both the most economical and the least polluting.
Propane? Natural Gas? Electricity?
There are several websites that address this topic, and the conclusions are often incorrect. Similarly, public opinion tends to mix concepts. Part of the reason for this confusion is the different units used for billing, which, combined with price differences, makes it difficult to see at a glance which system is more economical.
It is also sometimes said that one type of “heat” is worse than another, or that one costs more to heat than another. This, of course, is incorrect, because the feeling of comfort or the speed at which a building heats up depends exclusively on the heating system and its power, not on the energy source used.
To clear up any doubts, we present an example calculation made for an average household consumption of a 22 kW boiler, operating the equivalent of 120 hours per month at nominal capacity. However, the subsequent conclusions are independent of consumption, as they are proportional to it.
Below, we present the clear calculations, with all the different types of units involved, for the three types of energy sources.
We observe the following:
- Propane and diesel are similar, both in cost and CO2 emissions.
- Natural gas is 35% cheaper than propane and emits 29% less CO2.
- The direct use of electricity for heat generation (electric water heaters, electric radiators, and “blue heat”) is extremely inefficient from both an economic and environmental point of view, so its use should be avoided in all cases.
- In the case of using electricity to power a heat pump, it should have a COP of 2 to compete with propane, and a COP of 3 to match natural gas.
