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Medium Enthalpy Geothermal

I need to see the actual field data on medium and low enthalpy installations. The direct heat sources are between 200 and 1 km in depth, but there are a few examples where they provide heat for hundreds of houses in the US and Canada. I need to look into how direct source heating works for a project of this size, i.e., how to connect heating from the subsurface to many households.

A medium enthalpy approach would mean that many houses can be retrofitted all at once. This could be useful in new housing projects in more rural parts of the UK. One hole is dug for an entire housing estate, and all the heating is provided from there. You still need to address the installation issue. How can you connect them up easily?

Building sophisticated temperature models of the subsurface would be required here, but you can also start with some basics, without subsurface modeling. Another paper idea here would be a model that optimizes for surface heat from infrared satellite imagery and the projected areas of population growth to identify regions suitable for certain types of medium heat direct source heating.

This might help with some of the issues around cities. Although I don't think I fully understand the nuances behind city installations. I imagine there are quite a few issues regarding planning and general bureaucratic stuff.

The medium enthalpy installations are between 200-1000 m and temperatures between 25 and 150 degrees. Applications include

  • Aggregate drying
  • Onion and garlic drying
  • Fruit and veg drying
  • Mushroom culturing
  • Thermal driven chillers, refrigeration and ice making
  • carbonation of beverages
  • beet sugar evaporation
  • Cooking food processing and pasteurisation
  • Pulp and paper processing
  • Aqua culture
  • Lumber drying
  • Concrete block drying
  • Spas and recreational pools
  • Green houses
  • Soil warming
  • fabric drying
  • Direct space heating and domestic water heating

Ranking these by emissions/power use would be useful. For example, aggregates drying is very energy-intensive and quite inefficient.

There is potential for a solution like Cover with heating, where the installation and use of a geothermal source is very simple and easy to install in houses (not the houses themselves, though).

I need to look into the details about these wide-scale heating projects where entire villages are heated from the subsurface.

There is potential for many new housing projects, such as apartments and housing estates, to be linked up with a medium enthalpy heat source. Another project here could look at the number of houses that could be built in areas with geothermal potential from known subsurface temperature data.

I feel like you still run into many of the same issues in cities. This seems like a more efficient approach, instead of drilling shallow in many areas in a city, you drill deep in just a few and provide energy for the same amount.