How “Digital Twins” Are Enabling City-Wide Electrification

The City of Ithaca collaborated with Cornell University and RMI to model 5,468 buildings using a combination of the Urban Building Energy Model (UBEM) and the Green Upgrade Calculator (GUC). The analysis found that combining air-source heat pumps with envelope improvements and rooftop solar significantly reduces operating costs and electricity demand. The study identifies residential homes in low-income communities and certain downtown commercial buildings as high-priority targets for cost-effective decarbonization.

• Prioritizing building envelope improvements (such as insulation and window upgrades) before or alongside the installation of air-source heat pumps (ASHP) is essential for cost-effectiveness in cold climates like Ithaca. Without envelope improvements, monthly energy costs for commercial and residential buildings are modeled to increase by an average of $43; however, combining ASHP with envelope improvements reduces monthly operating expenses by an average of $330.
• Improving the building envelope reduces the required size of heating equipment from an average of 3.5 tons to 2 tons and limits the increase in community-wide electricity demand in an all-electric scenario to approximately 13%, compared to an increase of over 33% if no insulation improvements are made.
• Integrating rooftop solar with ASHP and envelope improvements significantly increases annual savings for property owners. For a pre-1980 townhome heated by natural gas, adding ASHP and envelope improvements saves $45 annually, but adding solar panels to that combination increases annual energy cost savings to approximately $1,742.
• The analysis identifies two primary high-priority building types for decarbonization: residential homes in low-to-moderate-income (LMI) communities, which offer high cost-benefit ratios due to the potential for complementary funding and the high impact of envelope improvements in older homes, and certain commercial buildings in the downtown area that offer high emissions reduction opportunities due to their large floor areas and high energy consumption.

APA

Tang, J., Tseng, H. M., & Dogan, T. (2024). How “Digital Twins” Are Enabling City-Wide Electrification. RMI. https://rmi.org/resources/how-digital-twins-are-enabling-city-wide-electrification/

Chicago

Tang, Jingyi, Hung Ming Tseng, and Timur Dogan. How “Digital Twins” Are Enabling City-Wide Electrification. RMI, 2024. https://rmi.org/resources/how-digital-twins-are-enabling-city-wide-electrification/.

Wikipedia

{{cite report |last1=Tang |first1=Jingyi |last2=Tseng |first2=Hung Ming |last3=Dogan |first3=Timur |title=How “Digital Twins” Are Enabling City-Wide Electrification |publisher=RMI |date=27 September 2024 |url=https://rmi.org/resources/how-digital-twins-are-enabling-city-wide-electrification/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{tang2024how, author = {Tang, Jingyi and Tseng, Hung Ming and Dogan, Timur}, title = {{How “Digital Twins” Are Enabling City-Wide Electrification}}, institution = {RMI}, year = {2024}, month = sep, url = {https://rmi.org/resources/how-digital-twins-are-enabling-city-wide-electrification/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }