Feasibility of Renewable Thermal Technologies in Connecticut

Yale Center for Business and the Environment is partnering with the Connecticut Green Bank, Eversource, United Illuminating and the Department of Energy and Environmental Protection (DEEP) to develop optimal policies and strategies that will advance renewable thermal technologies in Connecticut.


“Connecticut needs to be national, global leader on climate change” - Governor Malloy, Hartford Courant July 10th 2015. 


What is the potential contribution from Renewable Thermal Technologies (RTT) to help Connecticut achieving this ambition? How do the markets for these technologies need to be developed? What incentives are needed to attract more private investment in these technologies?  These are questions that will be studied in the research project “Feasibility of Renewable Thermal Technologies in Connecticut.

The 2013 Connecticut Comprehensive Energy Strategy mentions a whole range of measures to be taken within the fields of energy efficiency, industry, electricity, natural gas and transportation for Connecticut to be on the path to a cheaper, cleaner, and more reliable energy future. The strategy provides an important contribution to achieving the goal of an 80 percent emissions reduction by 2050, as spelled out in the state’s 2008 Global Warming Solutions Act.

In 2014 around 200 trillion BTU was used for thermal purposes in residential, commercial and industrial sectors in Connecticut [1]. Of that, roughly half was natural gas and 37 percent was fuel oil. Over 60 percent of the energy used in residential and commercial buildings is for space heating and cooling [2]. Changing from fossil fuels to renewable thermal technologies in heating and cooling buildings and industrial processes, has the potential of providing valuable contribution to Connecticut’s target of reducing greenhouse gas emissions to 80 percent below 2001 levels by 2050.

The project includes a broad specter of RTTs, which will be evaluated with regards suitability for achieving Connecticut’s long term goals and visions. Examples of technologies  are air source heat pumps, ground source heat pumps, solar thermal, biomass heating and district heating and cooling.

[1] Gronli, Helle; Fairuz Loutfi, Iliana Lazarova, Paul Molta, Prabudh Goel, Philip Picotte and Tanveer Chawla (2017): Feasibility of Renewable Thermal Technologies in Connecticut.  Market potential.

[2] 2013  Connecticut Comprehensive Energy Strategy


Feasibility Study Phase 1

The first phase of the research project quantified the thermal demand till 2050 and the potential and rational for RTTs within the scope of the market size. The research found that the potential market for thermal demand remains large, estimated to be the 100 – 140 trillion BTU range in 2050. The lower range represents a more ambitious building code for the commercial sector and a higher rate of deep retrofit in the residential sector. While our base case analysis assumes warmer winters and summers in 2050, the upper range of the demand projections represents a situation where we have the same outdoor temperatures as today.

There are both economic and non-economic barriers to this potential, such as high upfront costs, lack of awareness and installer business models. The research found several RTTs to be competitive to conventional electric technologies, while low fossil fuel prices in today’s market is a limitation. Achieving the targeted greenhouse gas emissions for 2050 is challenging though. The research found that a large share of RTTs which currently are not economically favorable to conventional thermal technologies has to be implemented to achieve the targets, in addition to the RTTs already being competitive. Reduced thermal demand through energy efficiency and de-carbonization of the electricity grid were also found to be important to get to the target.

The research of the project’s phase 1 is documented through two reports, which suggest a variety of solutions to increase the deployment of RTTs.   

Feasibility Study Phase 2

The second phase of the research project attempts to establish a framework of metrics, indicators and methods for monitoring the RTT markets across customer groups over time. This framework will be applied to set a baseline towards which market interventions can be evaluated. The research questions asked are:

1)         How to track the market?

2)         How to understand the customers?

The project will particularly focus on customer awareness, trust, technology deployment and market development. Although the framework and baseline will be developed to be generic, it will be built around the use-case “Thermalize” as a concept for reducing soft-costs.


Gronli, Lazarova, Loutfi, Molta, Goel, Chawla (2017): Market Potential

Gronli, Schiavo, Picotte and Mehr (2017): A field study on barriers and drivers.

Discussion paper on technologies

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