  The demand for electricity is undergoing considerable spatial and temporal
change. With the uptake of efficient technologies and increased
electrification, a better understanding of how potential changes in demand
patterns can affect network reliability is necessary. We quantify the
macro-economic impacts of potential future changes in demand profiles for an
electricity network undergoing generation shortages. Applied to Great Britain,
potential savings or losses are assessed for changes to peak demands under four
different load profiles: (i) current day, (ii) widespread uptake of efficient
appliances, (iii) deployment of heat pumps, and (iv) moving to an idealised
fully balanced load profile. Considerable variation in economic disruption is
observed both between different demand profiles and across Great Britain. When
the networks generation capacity is severely disrupted, we estimate hourly
macro-economic impacts to increase by up to {\pounds}1.23 million per
additional GW of national electricity demand. A similar reduction in impacts
can be achieved if peak demands are reduced by demand side management. We
conclude that risk-related economic impacts are directly linked to the temporal
pattern of energy demands and need to be included in the decision-making around
demand side measures. We find that decarbonisation strategies without
accompanying demand side management may lead to increased economic losses
without supply side interventions.
