9.7) Analysing: Subsidies

Having three good measures to observe PV adoption we can now include subsidies in the model. We will implement two possible subsidy mechanism; (i) an investment subsidy per m2 of installed PV, and (ii) a generation subsidy per kWh solar power generated. This will allow us to observe the impact of individual as well as bundled subsidy measures. Since we want to vary the value of these global variables we define them in the interface with two sliders.

• Name the investment variable subsidies-per-m2 and set its range from 0 to 200 with a increment of 20 and its value to 0 (as there is currently none in the UK). Name the feed-in variable subsidies-per-kwh and set the range from 0 to 0.3 with 0.01 increments and a current value of £0.15 / kWh solar power generated.

We now need to amend the calculate-balance-and-decide procedure to include the two subsidy schemes in the calculation.

• The installation subsidies per m2 will reduce the total costs of the installation, therefore subtract the subsidies from the costs per m2 in where we set the total costs, as follows:

let total-cost (PV-cost-per-m2 - subsidies-per-m2) * roof-size

• The feed in subsidies per kWh will add to the avoided costs of production (houses still use the electricity onsite). We therefore can extent the if statement in procedure:

if generation-cost-per-kWh < avoided-cost-per-kwh + subsidies-per-kWh [….]