Mepsy: The Appliance & Equipment Climate Impact Calculator
Analyze efficiency policy options for space heating equipment, ACs, refrigerators, motors, lighting, fans, and televisions
For efficiency policy practitioners, accurate data and predictive models provide insight into how policy decisions translate to real-world impacts
Setting policies and achieving their benefits requires accurate, actionable data. Mepsy’s dynamic, user-friendly interface guides researchers and policymakers in identifying efficiency policy opportunities and analyzing their energy and carbon impacts.
- Choose a country or region, product, and expected effective date to calculate policy benefits through 2050
- Use pre-loaded data from CLASP research and other sources, or enter your own data
- Download calculation results as a CSV file for further use
Mepsy calculates product energy use according to a “bottom-up” accounting approach which factors in the number of appliances in use in a country, the energy performance of representative products, the climate-intensity of the local power grid, and other variables to analyze the electricity use, carbon dioxide emissions, and consumer energy costs associated with a given policy scenario.
The tool supports policy analysis for space heating equipment, air conditioners, refrigerators, fans, motors, televisions, and lighting. Coming soon: residential water heaters, distribution transformers, and refrigerated display cases.
Explore global and national policy scenarios
Compare major global carbon emitters or select a country for regional analysis to explore a range of business-as-usual and efficiency policy scenarios for energy use, carbon dioxide emissions, and the number of appliances in use
See the CO₂ reductions, energy use, and number of appliances in use under business-as-usual or efficiency policy scenarios
Select a country to project the results of efficiency policy choices there and compare it with other countries in the region. Explore at the country level using the map interface, or dive deeper in the data for a single country.
Use pre-loaded data or input your own
The Mepsy model is based on a bottom-up stock accounting method that incorporates country-specific data on appliance energy use, markets, economic indicators and other policy factors
Data for Mepsy is drawn from several market research firms and other public and private data sources
Wherever possible, Mepsy references precise stock, sales, and energy performance data from recent CLASP in-country market studies, or country-level estimates from reputable market research firms. Where country-level data for a particular product are not available, calculations are based on estimates from regional or global averages, accounting for differences in country population, economics, or climate as relevant to a particular appliance. Future and past shipments are extrapolated based on recent trends.
View model outputs by country
At the country level, view customer-level policy impacts such as appliance lifecycle costs, as well as national-level changes to energy use, carbon dioxide emissions, and the number of appliances in use as a result of the chosen policy scenario
Mepsy's calculation methodology has been used for decades to evaluate efficiency policy options
The model inputs and results can be downloaded as a data file to support further analysis offline.
Analyzing policies with multiple tiers
Sometimes multiple-tiered policies need to be analyzed, where a package of increasingly stringent policies is implemented over several years. With the downloadable data, you can view combined impacts all in one place.
Combine multiple sets of data into one multiyear policy package with our how-to
Guides, Methodologies and Documentation
- Introduction to Mepsy
- Mepsy Quick-Start Guide
- How to Evaluate and Prioritize Efficiency Policies with Mepsy webinar – 27 April 2021
- How Mepsy Can Transform Your Energy Efficiency Policy Development webinar – 16 March 2022
- Mepsy Methodology and Assumptions – A summary of the methodology used for appliance model forecasting
- Methodology FAQ – More detailed explanations of the methodologies
- Extending Mepsy Past 2030 – Full methodology for our extension model (currently until the year 2050)
- Global Refrigerant Impact from 6 Appliances in 22 Countries – Full methodology for calculating the impacts of conventional refrigerants, to be integrated into Mepsy in the future
How Will Your Country Benefit From Banning Fluorescents?
CLASP recently updated Mepsy with the ‘African Lighting Amendment Scenario,’ demonstrating the national-level cost and energy savings if the world ends the manufacture, export and import of fluorescents by 2025. The scenario aligns with the proposed lighting amendment submitted by the African Region to the Minamata Convention on Mercury.