Copenhagen enjoys something we don’t have much of here in the United States: district heating. District heating is a service whereby hot water is delivered to homes and businesses, much like public water supplies are delivered here in cities and towns. Where it’s possible to implement a district heating utility, the savings and efficiencies are nothing short of remarkable.
Copenhagen’s main district heating distributor, CTR, serves much of the area, and does so at very high levels of efficiency. For example, imagine two identical areas with 250,000 homes, each of which demands 18,389TJ of heat annually. Area “A” uses what we’re familiar with: homes with oil-fired furnaces providing heat and hot water. Let’s also assume that each and every furnace runs at 90% efficiency (this would be a reasonable assumption if all furnaces in the area were all new, high-efficiency models…which many in the US are not). Area “B”, however, will opt for a district heating strategy, with no individual furnaces.
All other things being equal, Area “B” will meet the same heating demand as in Area “A”, but will use 94,573,600 fewer gallons of heating oil. This means several important savings:
- With today’s oil price at $3.179 in our area, this means a total fuel savings of $300,649,474, which translates to $1,202.60 per home in fuel alone
- With 250,000 fewer furnaces, each costing approximately $215/year to maintain, district heating would save consumers an additional $53,750,000 per year
- By avoiding burning 94,573,600 gallons of heating oil, district heating would reduce Area “B”s carbon emissions by 955,000 tons per year
Unfortunately, however, much of the United States (and Maine in particular) would not be a good fit for a district heating system identical to Denmark’s CTR. Maine is the least population-dense state in the union, with only 41.3 persons per square mile. This means that a district heating system at CTR’s scale would look like the following:
Moreover, unlike most of Denmark (and all of Copenhagen), Maine is located predominately on bedrock. This would make installation of the hot water mains much, much more expensive than the Copenhagen installation.
In short, while district heating makes a great deal of sense in Copenhagen, Maine would be hard-pressed to benefit from a similar system. Major cities in the US should consider such a system, as they have the requisite population density and subterranean utility infrastructure which would meet installation and efficiency goals.