A Synthetic Closed Carbon Cycle Energy System provides massive, long term, energy storage which supports low cost intermittent renewable sources and large seasonal power supply and demand variations.

摘要

Probably the biggest challenge facing the widespread uptake of low cost, but intermittent, renewable energy (RE) sources to provide a large proportion of our electrical power needs is the requirement for bulk energy storage. Some argue that intermittency can be mitigated using international grid connection because ‘the wind is always blowing’, or ‘the Sun is always shining’ somewhere. However, closer analysis reveals that whilst this view may be apt for demand (short- term) balancing it is an oversimplification for supply/generation (long-term) balancing. Sustained periods (days+) of reduced RE power generation, (e.g. UK - December 2010) would be difficult to balance if these RE sources provided a substantial proportion a country’s/region’s power generation capacity. Balancing this generation shortfall from imported renewables not only requires massive capacity interconnectors but also that the exporting countries have sufficient additional and guaranteed spare capacity available. An alternative is for countries to fill this shortfall using energy storage but this would require storing several TWh’s of energy for occasional use (yearly/seasonal); this requires long term, cheap storage systems because the low utilisation factor greatly increases amortisation costs. Currently the only practical approach is to use chemical energy storage, i.e. fuels, preferably liquid or solid, that have low capital storage costs. This presentation describes a novel, integrated, RE power generation infrastructure concept that incorporates such an energy storage mechanism, capable of providing long term, multi TWh, storage capacity at low cost. It is based on a ‘Synthetic Closed Carbon Cycle’ which stores energy in synthetically produced carbon or carbonaceous fuels made using cheap, or surplus, RE sources to regenerate fuels from captured CO2. This infrastructure also has several other benefits and importantly it could be integrated into existing power generation infrastructures.