Add ProcessHeat load, separate DHW and SpaceHeating loads

[zolanaj]

Added

• In src/core/absorption_chiller.jl struct, added field heating_load_input to the AbsorptionChiller struct
• Added new variables dvHeatToStorage and dvHeatFromStorage which are indexed on p.heating_loads and added reconciliation constraints so that dvProductionToStorage and dvDischargeFromStorage maintain their relationship to state of charge for Hot thermal energy storage.
• for all heating techs and CHP, added fields can_serve_space_heating, can_serve_dhw, and can_serve_process_heat in core structs and added new results fields thermal_to_dhw_load_series_mmbtu_per_hour, thermal_to_space_heating_load_series_mmbtu_per_hour, and thermal_to_process_heat_load_series_mmbtu_per_hour
• in src/core/techs.jl, added new sets ghp_techs, cooling_techs, techs_can_serve_space_heating, techs_can_serve_dhw, and techs_can_serve_process_heat
• in src/core/reopt_inputs.jl, added new fields heating_loads, heating_loads_kw, heating_loads_served_by_tes, and absorption_chillers_using_heating_load to the REoptInputs and BAUInputs structs. in the math, new set p.heating_loads has index q (to represent "qualities" of heat).
• In src/core/heating_cooling_loads.jl, added new struct ProcessHeatLoad
• In src/core/scenario.jl, added new field process_heat_load
• In src/mpc/inputs.jl, added new field heating_loads

Changed

• refactored dvThermalProduction to be separated in dvCoolingProduction and dvHeatingProduction with dvHeatingProduction now indexed on p.heating_loads
• refactored heating load balance constraints so that a separate flow balance is reconciled for each heating load in p.heating_loads
• renamed dvThermalProductionYIntercept to dvHeatingProductionYIntercept
• divided ThermalStorage into HotThermalStorage and ColdThermalStorage as the former now has attributes related to the compatible heat loads as input or output.
• changed technologies included dvProductionToWaste to all heating techs. NOTE: this variable is forced to zero to allow steam turbine tests to pass, but I believe that waste heat should be allowed for the turbine. A TODO is in place to review this commit (a406cc5).
• changed test values and tolerances for CHP Sizing test.

Fixed

• added a constraint in src/constraints/steam_turbine_constraints.jl that allows for heat loads to reconcile when thermal storage is paired with a SteamTurbine.

[zolanaj]

I'm thinking about user-friendliness and consistency with the thermal input versus the fuel input for the other heating loads. I forget if you mentioned the motivation for using thermal for process heat, but can you remind me? Most sites will still just have total gas load, and then they need to parse out the breakdown. It is common to have boiler capacities in terms of thermal output, but other than that it seems a little confusing to have a different way to input process heat.

Following up on our discussion this week, this is changed to fuel loads instead of heat in 14abae0

[zolanaj]

@Bill-Becker this should be ready for your review again. For some reason I'm not seeing your original review, but here are the key responses:

• The boiler retirement commits have been merged and updated to work with the new heating load disaggregation.
• Heat-specific storage output is now tracked via 679c7b5 and c0890d8
• ProcessHeatLoad is now given as fuel loads in input
• A new test suite tests disaggregation of heating loads, boolean logic for Boiler and ExistingBoiler's heating loads served, and the emissions reduction issue you set up (the fix for that is in fe4dd35)
• GHP's updates are summarized as follows:
  • GHP is now a heating tech and a cooling tech
  • The heating and cooling production for GHP are tracked in aggregate in dvHeatingProduction and dvCoolingProduction
  • Separate constraints reconcile the GHP option(s) selected and their compatible heating loads to calculate dvHeatingProduction and dvCoolingProduction in each time step

I'm running Xpress tests locally now and will update as needed if any tests are still broken after merging develop into this branch. Should I add the Process Heat test suite to the test_with_xpress.jl in parallel?

[Bill-Becker]

Thanks for clarifying and addressing my requests! I updated passing the user input boiler efficiency into ProcessHeat instead of always EXISTING_BOILER_EFFICIENCY, and I'm bypassing the Ubuntu tests until we can figure out why that one test is taking so long to solve that GitHub cancels the operation.