Abstract
This model explores the interaction between wet/hydronic central heating systems typical of the UK, and that will generally have to be retrofitted from gas-fired to heat pump by 2050, and TRVs (Thermostatic Radiator Valves) in those systems to micro-zone for comfort and efficiency. Heat-pump designers/installers have been concerned that while TRVs and zoning can lower heat demand, they may raise electricity demand (and thus carbon footprint) for the heating system. This model looks at various plausible UK scenarios at up to 1h resolution over 10 years, and indicates that the problem can indeed exist with very 'tight' temperature regulation, eg using "load compensation". But this "bad setback effect" goes away with pure "weather compensation", at the cost of looser temperature regulation.