Exploring synergisms and trade-offs

We are exploring the land-use needs and implications of meeting state goals for solar energy.

Gov. Baker proposed a “net zero” carbon emission goal during his January 2020 State of the Commonwealth address. The MA Executive Office of Energy and Environmental Affairs proposed a 2050 Decarbonization Roadmap Report to provide the Commonwealth with a holistic understanding of the strategies and transitions which are necessary in the near- and long-term to achieve Net Zero.

The Commonwealth’s decarbonization goals have implications for land use:

  • Energy supply – To meet the Commonwealth’s decarb goals will require significant deployment of solar energy on developed and undeveloped land across the state.
  • Working and Natural Lands – Carbon sequestration by forests, farms and urban agriculture, and soils can play an essential role in efforts to achieve net zero emissions. The state estimates that the Commonwealth’s forests have the capacity to sequester 5 million megatons of CO2 per year until 2050.
  • Transportation sector –Smart Growth development policies can help reduce vehicle miles travelled (VMT) across the state.


Current planning to achieve net zero emissions assumes that the Commonwealth will need to develop solar generation at scale, calculated on the low end as requiring 15-20 GW of installed ground- or roof-mounted solar photovoltaics, with 20-23 GW cited as optimal from a system-balancing perspective.

Ground-mounted solar development is the primary land use practice outcome of the Commonwealth’s decarbonization roadmap and has emerged as a significant portion (1/4 according to Mass Audubon) of total land development.

How much of the anticipated solar capacity can be gained from roof-top solar (including over parking lots)?  How much will have to come from other types of land – such as forests, farms, landfills, and brownfields?  How can the deployment of utility scale solar generation be balanced with opportunities for carbon sequestration by forests and goals for food security (and thus growing the farming sector)?  What are the equity implications of developing solar capacity in different regions of the state?

These – and other questions – are hotly debated and important questions.

Next Steps

With the collaboration of stakeholders we are developing a user-friendly systems dynamics model to explore the land use implications of solar energy deployment goals in Massachusetts.  The model will allow stakeholders to explore scenarios.  For example, in its simplest form:  how much capacity of solar energy can be achieved from different scenarios of land-use?  More complexity will be added to the model to allow the exploration of scenarios that include economic variables (such as costs of installation, subsidies), technology changes, and social factors (such as degree of opposition as more and more systems are installed).

The model is intended to foster discussion about critical questions for planning:  What are the equity implications of different scenarios?  What are the relative costs and who should pay for them?