Energy return on investment (EROI) of mini-hydro and solar PV systems designed for a mini-grid

With dramatic cost declines and performance improvements, both mini-hydropower and solar photovoltaics (PV) now serve as core options to meet the growing demand for electricity in underserved regions worldwide. We compare the net energy return on energy invested (EROI) of mini-hydropower and solar electricity using five existing mini-hydropower installations in northern Thailand with grid-connected solar PV simulations. Both assessments use a life cycle perspective to estimate the EROI. We find that distributed mini-grids with penetrations of solar PV up to 50% of annual generation can exceed the EROI of some fossil-based traditional centralized grid systems. The analysis will help planners and engineers optimize mini-grids for energy payback and utilize local resources in their design. The results suggest higher EROI ratios for mini-hydropower plants than solar PV, though mini-hydropower plants typically yield lower EROI ratios than their large-scale hydropower counterparts

Stakeholders’ Perspectives of Design Options for a Rooftop Solar PV Self-consumption Scheme in Thailand

Adoption of solar photovoltaic (PV) power generation systems has been accelerating around the world, contributing to the debate about the future of policy and regulation in a high distributed energy resources future. As one of the leaders in solar investment in Southeast Asia, Thailand has recently shifted its policy framework for the support of small scale, distributed solar PV systems from subsidizing power export through feed-in tariff toward a policy that is focused on self-consumption. This paper investigates stakeholder perspectives of the detailed design options for self-consumption schemes for supporting rooftop solar PV installations. The research methodology employed questionnaires and focus group discussion in order to capture stake-holder perspectives for each element of rooftop solar PV self-consumption schemes. In all, the data derived from questionnaires and focus group discussion involved a total of 72 stakeholders. The results indicate that most stakeholder groups expressed a strong desire for compensation for excess generation of PV electricity from rooftop PV systems. While the majority of electric utilities prefer a system of net billing with real-time buyback, designed to minimize revenue losses, consumers and policymakers preferred a net-metering-based compensation scheme for supporting use of rooftop PV electricity in Thailand

Preliminarily Screening Geographical Hotspots for New Rooftop PV Installation: A Case Study in Thailand

As rooftop PV deployment accelerates around the world, forecasts of rooftop PV penetration by geographical region and customer group are essential to guide policy and decision-making by utilities. However, most state-of-the-art forecasting tools require detailed data that are often unavailable for developing countries. A simplified analytical tool with limited data is proposed to preliminarily identify the rooftop PV “hotspots”—that is, geographical areas where many new investments into rooftop PV investments are likely to occur. The tool combines the assessment of financial and technical indicator in form of the optimal PV-to-load ratio indicating the maximum penetration of solar PV, and the capital-to-expenditure ratio indicating the ease of such investment. Using Thailand as a case study, the results from this tool show that under the self-consumption and net-billing scheme, the Northern and Northeastern regions are marked as the potential hotspots where the utility’s impact will be realized early or strongly or both. The average LCOE and self-consumption level for all customer classes and regions are in the range of 0.084–0.112 USD/kWh and 41.33–73.13% of PV production, respectively