The 4 SKIES solution proposed for Repurposing Pickering mainly highlights the transformation from nuclear power to natural gas power by replacing at least 4 of the 8 existing nuclear reactors now in place at the Pickering Nuclear Power Plant. With a total net capacity of 2,000 MW to the grid, the output will be less than half of the original Pickering plant’s capacity, but given the recent reduction in demand for electricity across the province, this capacity level may be ideal for the foreseeable future.
However, given that a sizeable land area is available and it will not likely all be used in the project, 4 SKIES would recommend installing other smaller scale renewable energy systems onsite to take advantage of those portions of land not used by the natural gas plant and greenhouses, to include wind, solar, and possibly biomass. Although there may be room for commercial-scale, traditional forms of renewable energy systems, it would also be worthwhile to integrate non-traditional, renewable, and clean energy systems, such as bird-friendly wind turbines, building integrated photovoltaics (BHPV) and even solar street lighting with integrated wind turbines.
To compliment the production of 100,000 metric tons of produce from the greenhouses, an anaerobic digester could be installed to process the organic waste from the greenhouses into biogas for use as fuel in a small Combined Heat and Power (CHP) plant to produce heat and electricity for the greenhouse operation. Depending on how much biofuel is produced, some of the biogas can be cleaned, compressed and sold as fuel for cars and trucks equipped to run on natural gas. If heat is not required for the greenhouses because ample heat is being supplied by the natural gas plant, another option might be to utilize the biogas in fuel cells installed onsite to generate and supply electricity to the greenhouses.
Of course the added benefit of nutrient rich compost and bio-fertilizer derived from the digestate material removed from the anaerobic digester can be reused in the green house operation, or sold to local garden centres, and possibly even sold to local farmers as feed for livestock.
Although organic waste from the greenhouse operations is considered biomass, another rapid growing organic organism is algae, which can absorb more CO2 than most plants and in a shorter time. In fact one kilogram of microalgae can capture nearly 1.83 kg of CO2 and can yield up to a hundred times their yield weight per year than food crops. Some algae can even have two harvest seasons in one day. The most important product from algae is biodiesel and the biomass can be processed into healthy food, animal feed, biogas and fertilizer. The CO2 concentration in the flue gas from the power plant is about from 10% to 20%, otherwise the CO2 concentration in the atmosphere is around 380 ppm. In order to capture the CO2 from the flue gas, the microalgae species used in the capture process must grow efficiently under the condition of the high CO2 concentration. In order For the “Repurposing Pickering” project to be completely free of CO2 emissions, 4 SKIES realizes it will need to be creative in this pursuit. Algae is just another option that will be considered and will no doubt require further study.