Negative emissions farm EmissionPenalty #99
Description
@Timon-R has identified that use of EmissionPenalty subsidises negative emissions, resulting in energy system models "farming" negative emissions to reduce the total energy system costs.
@FraGard suggests the following solution modifying the E5 constraint to only be active for positive values of EmissionAcitivityRatio, e.g. adding : EmissionActivityRatio > 0
Change:
s.t. E5_DiscountedEmissionsPenaltyByTechnology{r in REGION, t in TECHNOLOGY, y in YEAR}:
sum{e in EMISSION, l in TIMESLICE, m in MODE_OF_OPERATION}
EmissionActivityRatio[r,t,e,m,y]*RateOfActivity[r,l,t,m,y] * YearSplit[l,y] * EmissionsPenalty[r,e,y] / DiscountFactorMid[r,y]
= DiscountedTechnologyEmissionsPenalty[r,t,y];To:
s.t. E5_DiscountedEmissionsPenaltyByTechnology{r in REGION, t in TECHNOLOGY, y in YEAR}:
sum{e in EMISSION, l in TIMESLICE, m in MODE_OF_OPERATION: EmissionActivityRatio > 0}
EmissionActivityRatio[r,t,e,m,y]*RateOfActivity[r,l,t,m,y] * YearSplit[l,y] * EmissionsPenalty[r,e,y] / DiscountFactorMid[r,y]
= DiscountedTechnologyEmissionsPenalty[r,t,y];