Massive geothermal apartment complex is going up in Brooklyn, first of its kind
cnbc.com
cnbc.com
The entire neighbourhood of about 2200 houses is heated and cooled by this installation.
About 60% comes from the heat pumps that get their water from two well pairs, about 40 and 80 meters deep. It's not a closed system and the ground water flows about 50-100 meters to either pair.
The remaining capacity comes from a gas turbine that generates electricity to sell back to the net, and the residual heat is captured and used to heat the district. If the demand isn't there, it's pumped back into the ground for future use.
The third method is what amounts to basically a giant electric kettle, which has the worst COP factor, but there are times here in The Netherlands when energy prices are negative, and that's when they shut down the gas turbine and use the electric heater instead.
There are three pipes going to every house in the district, one with hot water, about 70 degrees and used for both floor heating and hot water, one with cold water for cooling in the summer, and a return pipe.
It removes a lot of infrastructure from your house, the hot water goes directly in your floors, so no boilers or furnaces. There's a small heat exchanger that warms the tapwater for showers, and you have zero maintenance.
Underfloor heating? Is that not too hot to walk on???
Or is some kind of in-house heat exchanger used?
What i dont understand is how it is efficient to deliver a constant 70 degrees heating pipe. There has to be some kind of boiler/trigger right?
The pipes are well insulated and apparently the energy loss quite manageable.
Depending on the specifics, that's often about 5x more efficient.
Counterintuitively - the "heat" source doesn't have to actually be hot. In theory as long as it's above absolute zero it can be used as a heat source to heat up the inside of your home. It's the same for cooling - even if it's hot indoors and really hot outdoors, you can still use a heat pump to make it even colder inside the hosue.
We have that at home, this is great. No noise, no maintenance, no emissions. The only downside is that you are "locked in" with a single heat provider.
I suppose new installation don't have the issue, but for stuff I'll use for a long time (basically house, computer and car), if I don't know how to repare it, I prefer old tech.
> About 9 % of the total heat demand in Germany is covered by heat grids today and 14 % of the demand for residential buildings.
https://get-green-now.com/geothermal-energy-vs-ground-source...
Edit: was this a new from scratch development or a retrofit? I realize my plumbing question might be irrelevant.
Ground source heat pumps use the soil or ground water as a low temperature mass to draw heat from. Surface soil follows air temperature, with a lag because of its high thermal mass. Below a meter or so this lag becomes so large that it just stays at the annual average of the air temperature. So the heat is not coming from the earth below!
I would reserve the word "geothermal" for projects that actually access high temperature sources, where the heat does actually "come from below".
The concept seems more related to Thermal Mass than geothermal energy. https://en.wikipedia.org/wiki/Thermal_mass
I’m fascinated by Eathships which rely on this along with convection to regulate air temperature. https://en.wikipedia.org/wiki/Earthship
It would be really cool (pun) if the much more widely available low enthalpy option could produce electricity but it seems that this in not possible (yet?). High enthalpy plants have a range of complications as the fluid being used is full of chemicals.
[1] https://en.wikipedia.org/wiki/Geothermal_heating
[2] https://css.umich.edu/publications/factsheets/energy/geother...
My first thought was whether heat demands would overwhelm the capacity of the ground, but I read that soil has a thermal mass about 1/5th of water so a rule of thumb might be that you don’t have to worry unless more than about 15% of the total volume underground is replaced with heat pipes, which it is definitely not (first concrete numbers I could find suggested 10cm boreholes spaced 5 meters apart, which is less than 1% of ground volume).
https://newyorkyimby.com/2023/01/excavation-and-pilings-cont...
It says the swimming pool will be heated with geothermal energy. Would not that make the temperature cold? It would be better to use solar power to heat the pool.
Heat exchangers should be given a heavier role here. Heat emissions from the refrigerators plus air conditioners should heat the central water heater and boilers.
I have often thought about the idea of using heat from refrigerators but I think that would be more trouble than it's worth for small domestic fridges. But definitely if they have this ground source system, they use that as a shared heat reservoir that the heat pumps air conditioning apartments in summer reject heat into and the heat pumps heating hot water draw from.
1. You get passive cooling in the summer 2. The greater the temperature difference is the more efficient the pump becomes so they are more efficient even in not so cold weather 3. The maintenance costs of the system are significantly less. You need to clean and replace blower fans. Cleaning has to be done yearly or twice yearly depending on environment. Ground source, you only need to maintain the pump and coolant which needs replacing cca once every 20-30 years.
Cheap method for smaller houses!
There are apartment buildings going up in NYC with one-pipe steam heat, steel pipes, and cast-iron radiators, because there is nothing outside the boiler room worth stealing.[1]
Is there a source for that? You build the rest of your conjecture on this unsourced claim...
> Lendlease acquired $4 million in support from the New York State Energy Research and Development Authority (NYSERDA) to build a geoexchange system at 1 Java Street.