Net Zero UK – Generation and Energy Storage Requirements for the UK to Become Carbon Neutral

This paper sets out a quantified scenario for the UK to reach net zero carbon emissions. Wind and solar are the main energy sources and their intermittency is accommodated through hydrogen electrolysis, biogas from anaerobic digesters, and their combination into biomethane. Hydrogen and biomethane stocks are tracked. A daily energy balance model is presented, using the most recent recorded weather data-2017 to 2021. Long periods of low wind in 2021 indicated the necessary energy storage capacities, which were adjusted relative to energy generation capacities so as to achieve an economic minimum cost. The projected levelized cost of electricity is £92/MWh (which is well below the current energy wholesale price of £130) though this does assume greatly improved thermal insulation of most UK buildings. A 10% reduction of this cost is shown to be possible through the application of demand side management (retiming of energy consumption) thus illustrating the value of such flexibility. Carbon capture and storage (CCS) applied to power stations running on the biomethane could provide up to 21 Mt of negative emissions to offset other sectors, imports and even remove some of the excess emissions that have already occurred. The work goes beyond previously published scenarios: energy pricing is calculated, demand response measures have been modelled, and embedded carbon in imported goods is considered. The Python model is available, open-source, for inspection and further development.