Qualitative Measures

Impacts

This metric is qualitative and rather site-specific and will take into account and environmental, social and health impacts associated with the system. The following is a list of possible impacts which could be considered:

For the study undertaken, a 200 home district in a suburban area was considered, so an impact such as loss of business due to construction was not considered. All other impacts were considered.

End User Costs

As we have seen in the "costs" section above, key in calculating the viability of a system is the sell price of the energy to the end user. As the buy price of fuel/electricity cannot be altered, one of the ways in which the project developer can increase profits is to increase the price at which they sell the energy.

However, for a particular district heating system to be desirable the end user must feel that they are getting value for money. A customer is unlikely to enter into a contract which is not at least of equal value to their current contract, unless they have a particular interest in "going green"; therefore the viability of the system will partially depend on this, and a balance must be struck.

This metric is qualitative and will be based upon a comparison between the sell price of the energy and average gas prices in the UK.

Income/Subsidies

Some district heating systems may be more viable for government subsidies than others; for example, at the time of writing, the only kind of boiler-based district heating system eligible for Renewable Heat Incentive payments would be biomass-fueled. To evaluate this metric, governmental incentive schemes will be looked at and the available subsidies will be examined thoroughly. For the 100% renewable electricity powered system, an estimation of the projected subsidies will have to be made, which may be difficult to estimate accurately.

In addition to governmental subsidies, systems themselves can generate additional income - for example CHP systems generate electricity which can be sold (in addition to earning generation and export tariffs), biomass boilers produce ash which could be sold as fertiliser, and storage heaters could take advantage of cheaper nighttime electricity tariffs.

Both government subsidies and possible streams of additional income will be assed together qualitatively.