Optimization of a Renewable Energy Generation Capacity for Off-Grid Communities
Remote, off-grid, communities in Canada typically use diesel generators to supply their electricity. Diesel generation is both expensive, carbon intensive, and transportation of fuel presents environmental risk due to spill potential. Renewable energy systems can be integrated with diesel generators and can mitigate environmental risks in addition to saving communities money. To find out if ocean wave energy converters can be viable as contribution to hybrid diesel-renewable systems for remote communities, a case study is underway at Hot Springs Cove. There are renewable resources nearby: Wave energy is plentiful; wind speeds are favourable; There is a potential for installing a small run of river plant at a local creek. In this case study, we are using an optimization algorithm iteratively over an entire year of hourly power dispatch to find out what levels of installed wave, wind, and run-of-river capacity (kW) will minimize the levelized cost of electricity [$/kWh]. The cost of wave energy converters is highly unknown because wave energy conversion is an immature technology. To address that issue, we have run the optimization for various wave energy costs for installed capacity.. Preliminary results are shown in plots A, B, and C for wave power installed costs of 3000 [$/kW], 5000 [$/kW], and 8000 [$/kW] respectively.
In the plots, the objective function of the optimization is shown by the 3D ‘iso-surfaces’ of constant levelized cost. The darker the color, the lower the levelized costs. The optimization result is shown by the white diamonds with red outline. We can see how increasing the cost of wave energy tends to push wave energy out of the optimum renewable energy capacity. The following table is a summary of sum of the preliminary results.
It is clear that a renewable energy system installation at Hot Springs cove could curtail significant diesel fuel use and CO2 emissions. Given the assumptions of the study, the cost at which a wave power system becomes economic in an optimum renewable-diesel hybrid scenario is just over 5000 [$/kW]. A detailed report of the data sources, assumptions, methods, and further results of the case study are to be published Spring 2014 in a forthcoming journal article.