65% of Denmark’s heating needs are covered by heat networks and 1.85 million homes are already connected. This will change significantly by 2028, when around 300,000 more properties are expected to become part of the heat network family.
Properties with natural gas and oil will need to switch to green heating, and heat networks is a top priority where technically and economically feasible. This was decided in 2020 and should happen by 2030. However, then came the war in Ukraine and energy policy turned into security policy. Two years were cut from the target, and Denmark must now be free of Russian coal and natural gas for heating by 2028.
Heat network conversion not seen since the 1970’s oil crises
What we see now is a huge conversion of both the Danish heating infrastructure and the heat network sector. And it can only happen too slowly. Many households want to be on heat networks sooner than 2028, and most probably will. But heat networks roll-outs take time, with sensible planning, development, and connection. Projects should not be set up that lead to debt or poor economics.
From 1987 to 1996, 400,000 oil-fired homes were converted to heat networks in the wake of the great oil crisis. The sector has therefore proved that it can be done, but ambitious heat networks companies are not enough. It is also about the whole supply chain, politicians and authorities being prepared to take on the challenge. The authorities must be able to follow and approve the projects, and there must be access to materials, tradesmen, and capacity all at a sensible price.
Heat networks powered by green gas
As well as having to convert natural gas in individual heating, the heat networks sector is also facing the phasing out of natural gas consumption in heat network production.
Coal is close to being phased out in heat network production, while natural gas continues to be used at around 12 percent. The reduction of natural gas is already well underway in line with the green transition and the process has been accelerated in light of the Russian natural gas embargo and high natural gas prices.
Heat networks are thus moving away from fossil heat sources and into production based on new, future-proof forms of energy such as solar heat, large heat pumps, waste heat, electric boilers, geothermal energy, renewable biomass, and waste energy. Here it is important not to forget the important role of CHP plants in both providing secure electricity as well as supplying waste heat for heat networks. A power system based only on solar and wind power is unreliable when there is no wind, or at night. Therefore, large, and small CHP plants co-producing electricity and waste heat for heat networks must be maintained with a production based on green gas, renewable biomass, and biodegradable waste.
Heat network knowledge, technology and skills will be a major export
The development of heat networks will not stop in Denmark in 2028 or 2030. Exciting new things like digitalisation and better user experience, as well as energy optimisation with many new low energy buildings are expected. The amazing thing is that heat networks have a very high share of employment from industry, consultants, and national suppliers. The sector is also looking at a big export opportunity when the rest of Europe needs heat networks to achieve their goal of phasing out Russian natural gas and converting to a green heating system.
Source: Written by Kim Behnke, Development Manager, Danish District Heating for HVAC magazine edition 10 2022