Environmental analysis of a Concentrated Solar Power (CSP) plant hybridised with different fossil and renewable fuels

The environmental performance of a 50 MW parabolic trough Concentrated Solar Power (CSP) plant hybridised with different fuels was determined using a Life Cycle Assessment methodology. Six different scenarios were investigated, half of which involved hybridisation with fossil fuels (natural gas, coal and fuel oil), and the other three involved hybridisation with renewable fuels (wheat straw, wood pellets and biogas). Each scenario was compared to a solar-only operation. Nine different environmental categories as well as the Cumulative Energy Demand and the Energy Payback Time (EPT) were evaluated using Simapro software for 1 MWh of electricity produced. The results indicate a worse environmental performance for a CSP plant producing 12% of the electricity from fuel than in a solar-only operation for every indicator, except for the eutrophication and toxicity categories, whose results for the natural gas scenario are slightly better. In the climate change category, the results ranged between 26.9 and 187 kg CO2 eq/MWh, where a solar-only operation had the best results and coal hybridisation had the worst. Considering a weighted single score indicator, the environmental impact of the renewable fuels scenarios is approximately half of those considered in fossil fuels, with the straw scenario showing the best results, and the coal scenario the worstones. EPT for solar-only mode is 1.44 years, while hybridisation scenarios EPT vary in a range of 1.72 -1.83 years for straw and pellets respectively. The fuels with more embodied energy are biomethane and wood pellets.

Technology transfer of renewable energy for rural development: historical evolution and lessons of experience from the model WWP

Technology transfer (TT) in the area of renewable energy (RE) throughout history has been an important tool for rural development (RD). Initially, the TT has been conceptualized as the purchase or donation of machinery from first world countries - without any consideration of staff training and contextual conditions for the adaptation of technology to the needs of the country. Various researches have revealed the existence of different approaches to planning the TT of RE, demonstrating the high complexity of projects from the social and contextual dimension. This paper addresses the conceptual evolution of the TT of RE for RD, examining its different periods considered for three criteria: historical events occurred, the role of stakeholders and changing objectives for the TT of RE for RD. For the conceptual analysis of changes the model Working With People (WWP) is used for planning and project management of high social complexity in RD. The analysis defines the existence of four historical periods in the TT of RE and synthesizes the lessons of experience from the three dimensions (ethical-social, technical-entrepreneurial, and political-contextual) of the WWP model.

Cost-free feed-in tariffs for renewable energy deployment in Spain

Feed-in-tariff (FIT) schemes have been widely employed to promote renewable energy deployment. While FITs may be perceived by consumers as an extra cost, renewable energies cause a noticeable price reduction in wholesale electricity markets. We analyse both effects for the case of the Spanish electricity market during 2010. In particular, we examine the level of FITs that makes savings and extra costs to be similar on an hourly basis. Results are obtained for a wide range of renewable generation scenarios. It is found that FITs with null extra costs for consumers are in the range of 50–80 €/MWh. Some of the side-effects of a high penetration of renewable energy in the market are analysed in detail and discussed.