I have created two pathways combining parts of the High Nuclear and High renewable pathways that DECC has published, one using renewable supply side elements and nuclear demand side elements as below;
The other using Nuclear supply side elements and Renewable demand side elements
In summary, by using the nuclear supply side and renewable demand side it results in a pathway which is cheaper than all other example pathways (bar Markal); it also reduced emissions to 9% of 1990 levels (72 Mtonnes CO2e). On the converse side the renewable supply side and nuclear demand side resulted in a pathway which was more expensive and with emissions at 33% of 1990 levels (268Mtonnes CO2e). These two pathways also highlight the importance of energy efficiency
While I believe that renewables generation will have a substantial role to play in electricity generation in the future as part of a balanced energy mix, I also believe that supply side options should be costed to meet the same demand base so as not to deliver a result which may be unclear. A degree of variation could be applied to the demand level across all supply side bases to give a sensitivity analysis across a range of scenarios.
I also believe a model with a fixed demand side could be a useful tool for more engagement with the public as it would give greater clarity over the potential for different supply mixes to meet the 2050 targets in an economic way.