Sustainable Solar Siting in Connecticut: Ecological, Energy, and Economic Trade-offs
Adam Gallaher, Sarah Klionsky, Yan Chen
Renewable portfolio standards (RPS) aimed at reducing greenhouse gas emissions have sparked the development of renewable energy across the United States. For example, Connecticut has set a mandatory RPS target of 44% by 2030, with 40% from class one renewables (CT Energy Plan 2018). However, as of 2017, only 12.9% of Connecticut’s electricity came from class one renewables (EIA 2020). RPS targets begin to increase by 2% per year (CT Energy Plan 2018) beginning in 2021, requiring aggressive procurement of renewable energy to meet targets. The deployment of ground-mounted, utility-scale solar energy has been a popular option for meeting mandated targets. As solar development increases, it is important to consider trade-offs between land uses, ecosystem services, and the effect of public perception toward renewable energy projects (Pasqualetti 2001; Russell et al. 2021). We will use spatial analyses and land use, ecosystem services, and energy models to answer the following questions:
- Considering electricity infrastructure, ecosystem services, energy production, and economics, where are optimal locations for ground-mounted, utility-scale solar siting in Connecticut?
- How do municipalities around Connecticut perceive ground-mounted, utility-scale solar development, and how do community characteristics and previous experience with solar development influence those perceptions?
- How do solar siting scenarios change under future land use forecasts?
The research questions and proposed methods were informed by a series of stakeholder meetings. To evaluate the tradeoffs between ground-mounted, utility-scale solar energy production and ecosystem services in Connecticut, we will use a multi-step process that integrates results from multiple models and will result in a real-time and forecasted techno-ecological-financial output. The final output is a series of maps used by stakeholders to evaluate sustainable locations for solar development in Connecticut. The steps are:
- Forecast LULC using Clark University’s TerrSet Land Change Modeler.
- Develop conditional scenarios for suitable solar sites.
- Estimate solar energy production and cost using the National Renewable Energy Laboratory’s System Advisory Model (SAM).
- Estimate some ecosystem services using the Natural Capital Project’s InVEST models.
We have also developed a survey aimed at assessing the perceptions of solar energy within Connecticut communities that will be used alongside the model to help contextualize the social dimensions of solar energy.
We have met with many stakeholders and experts from public agencies, organizations, and academia. Our efforts have resulted in an ongoing data collection process to create a spatially explicit dataset built from data sources specific to Connecticut such as: land use land cover, land features, weather, ecosystem services, and energy data. We are currently in the process of testing the models that we will, ultimately, combine for our final analyses. Once the workflow of our model is complete, we will begin reconnecting with stakeholders for input in setting decision-making criteria.
In conjunction with an Eversource Energy Center project, we are finalizing a survey that will be distributed to municipal leaders/employees around Connecticut to gauge public perception of ground-mounted, utility-scale solar development.