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As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
Best part is you don't even care about heat loss because you're trying to get rid of all that heat anyway.
This scheme has been inplace since the 60's. https://en.wikipedia.org/wiki/Ljubljana_Power_Station
District Heating is quite popular in much of the world. USA built the first such system back in 1853. https://en.wikipedia.org/wiki/District_heating
The whole thing seems so inefficient but I am not an expert. Can anyone here expand on this?
As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
Also, as made famous by the many steam vents in NYC movie shots: https://en.wikipedia.org/wiki/New_York_City_steam_system.
More info: https://en.wikipedia.org/wiki/District_heating#United_States
As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
I think that's mostly due to the high upkeep costs of the system, though, the transmission loss is quite manageable, I think. Of course there are arguments to be made that when accounting for the cost of installing a heating system, and the space it takes, the premium paid for district heating is not that high.
But still... if district heating is so smart, why ain't it cheaper?
What's nice about it, and maybe hard to quantify, is how this limits air pollution in the city. However, people are still allowed wood burning ovens... which they are now all turning to since the district heat is getting really, really expensive..
As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
It only works well when heating is 'free' - such as when you're using waste heat from a nuclear power plant, or from overproducing solar/wind plants.
- water has 5x the specific heat capacity of sand
- water can be pumped around easily
- water can be used directly for district heating
As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
Faster hot water incentivizes hand washing. Just think about how many more people would wash their hands at the airport if they didn't have to wait 2 minutes (or forever) to get hot water.
The whole thing seems so inefficient but I am not an expert. Can anyone here expand on this?
As an American it completely breaks my expectations that district heating not only works can be more efficient that decentralized heating. The amount of heat lost just moving water from the water heater on one side of the house to the shower on the other is ridiculously high in houses here. The idea that you can insulate well enough to efficiently move heat across a city is amazing to me.
Most household water pipes really aren't insulated, or aren't insulated well enough. Plus, moving water under the frostline means that the ground it's moving through might be upwards of 55 degrees F.
My house came with an outdoor wood boiler (it's more a rural cabin than a house, really). It moves 180*F water from the boiler 50 feet underground into the house, where it runs through an air exchanger in the central air system and pipes it back out to be reheated.
Newer models of these things can get upwards of 98-99% burn efficiency, and ~85% heat transfer efficiency- as good as or better than you can get with standard efficiency furnaces.