Solar Concentrating Steam Generation in Alberta, Canada

Abstract: In the context of climate change the world is facing an increasing need to become more environmentally sustainable, and a concerted effort to use renewable energy is required in order to decrease emissions, meet climate goals and prepare for the post-oil era. Solar energy is an area with great potential, and developments in solar energy technologies have increased rapidly. Concentrating solar technologies have existed for more than one hundred years, and have largely been applied in the context of direct power generation. However, solar energy technologies can also be used for purposes other than power generation, such as generating steam for alternative applications. This work investigates the steam generating potential of a solar steam generation system located at the Southern Alberta Institute of Technology (SAIT) campus in Calgary, Alberta, Canada and the potential for utility scale implementation in Alberta’s Oil Sands for steam demanding enhanced oil recovery (EOR) methods. Furthermore, this thesis also validates weather data for the SAIT campus. Both of the proposed systems use parabolic troughs as solar collectors. The SAIT system also incorporates a two-tank direct thermal energy storage and Therminol 62 as the heat transfer fluid, while the utility scale system uses water as the heat transfer fluid. The results show that the SAIT system can provide saturated steam at 0,7 MWh 155 times which amounts to a total steam output of 90 MWh annually. The results for the utility scale system show that solar steam generation from a 500 MW thermal plant implemented for enhanced oil recovery in an EOR facility becomes economically feasible, as compared with steam production from natural gas, at a natural gas delivery price of approximately $7 USD/GJ. Furthermore, an installed 500 MW thermal plant can reduce carbon emissions by 180,000 tonnes of CO2 equivalents annually. Conclusions drawn in this thesis are as follows: the technology is technically feasible however there are both political and economic obstacles to its use; solar EOR should be seen as an add-on to existing plants due to the intermittence of solar energy in Alberta; the GHG reduction potential is great and consequently there is a possibility of receiving carbon credits by using the technology; and by tilting the solar collector field total output can be increased by over 25%.