History of LEAP

See also: Introduction, Getting Started, Credits

Origins: 1980s

LEAP was originally created in 1980 for the Beijer Institute's Kenya Fuelwood Project, to provide a flexible tool for long-range integrated energy planning. LEAP provided a platform for structuring data, creating energy balances, projecting demand and supply scenarios, and evaluating alternative policies, the same basic goals as the current version of LEAP. Major funding was provided by Swedish SIDA, German GTZ, the Government of the Netherlands (DGIS), and US-AID.

LEAP was originally implemented on a mainframe computer. In 1983, with funding from US-AID, it was converted for use on a minicomputer and a first user-interface was added with the aim of transferring it to energy planners in Kenya and elsewhere. By 1985, LEAP had been ported again, this time to the newly emerging IBM PC microcomputer, making wider dissemination and a more user-friendly interface possible. In the course of the 1980s, LEAP-based studies were conducted in a dozen countries in Africa, Latin America, and Asia.

1990s

In the 1990s, with concern about the environmental impact of energy systems growing, LEAP became one of the first energy modeling tools to address this concern through the addition of the Environmental Database (EDB) and enhancements for computing emissions loadings in LEAP. The United Nations Environment Programme provided major funding for this phase of development.

The early 1990s saw a broadening of LEAP's user-base. In 1991, the first major LEAP-based study of an OECD country was conducted "America's Energy Choices": an analysis of the potential for energy efficiency and renewables in the USA. In 1992, the first global energy study using LEAP was published titled "Towards a Fossil Free Energy Future" (a report to Greenpeace). Meanwhile, studies continued throughout the developing world, including a World Bank sponsored project to integrate LEAP with an emission dispersion model for studying air quality in Beijing.

The spread of the Internet in the mid-1990s allowed for much wider dissemination of LEAP. With the issue of climate change rising on the international agenda, LEAP was further enhanced as a tool for Greenhouse Gas (GHG) mitigation assessments. Many countries used LEAP  for their national communications to the UNFCCC, and for their contributions to the U.S. and UNEP Country Studies Programs on Climate Change.

By the late 1990s, with support from the Dutch Government (DGIS), a new Windows-based version of LEAP was created, allowing the original goal of a highly user-friendly energy and environment planning tool to be more fully realized. The first version of the new tool was made public in early 2001.   

2000s

By 2003, with the number of LEAP users reached 500 with most in the developing world.  A new project was launched to upgrade the support provided to these users and to foster a community among Southern energy analysts working on sustainability issues. With support from DGIS, a new web-based community (leap.sei.org ) was created.

2004 saw the introduction of multi-region modeling capabilities, allowing users to divide an area into multiple region.  By early 2006 the number of participating LEAP users had grown to over 1500 in more than 130 countries.

2010s

2011 saw LEAP's modeling capabilities being significantly expanded with least-cost optimization modeling based on the GLPK open source mathematical programming toolkit and the OSeMOSYS energy modeling system being added to LEAP's existing accounting and simulation modeling capabilities.  2011 also saw the first global LEAP model being constructed for the SEI study "Energy for a Shared Development Agenda: Global Scenarios and Governance Implications".  This report was published as part of SEI's contribution to the Rio+20 conference.

By 2012, LEAP's users numbered more than 15,000 in 190 countries.  2012 also saw the introduction of new features allowing LEAP to be linked to SEI's WEAP model in order to support energy-water "nexus" modeling analyses.

2013 saw LEAP being upgraded and improved in order to support a new type of analysis focused on supporting national action planning on Short-Lived Climate Pollutants (SLCPs).    This type of analysis required significant improvements to LEAP's User Variables feature to make LEAP more extensible and flexible, especially for non-energy sector analyses.

By 2014, the number of users had reach 22,000. The 2014 version was much faster in terms of its calculation speed and provided new facilities for supporting the interactive use of LEAP in stakeholder settings, for example through the new Scenario Explorer feature, and a new full screen mode.  It also provided much more powerful support for optimization modeling, by supporting IBM's CPLEX solver and through improved cost-benefit calculation capabilities.

By 2015, the number of users had reached 26,000.  The 2015 version added new data visualization methods including a new Sankey Diagram as well as improved performance and better usability.

By 2016, the number of users had reached 32,000.  

By 2018, the number of users had reached 36,000 in 195 countries and territories. Highlights of the 2018 version of LEAP included:

2020s

By 2020, the number of users had reached 44,000 in 198 countries and economies. Highlights of the 2020 version of LEAP include:

  • The NEMO framework for Optimization modeling.
  • Energy storage modeling and redesigned time-slicing.
  • Indoor air pollution health impacts modeling.
  • Marginal Abatement Cost Curves (MACCs).
  • IPAT-based Decomposition reports.
  • Map-based Geographic projections of energy use and emissions.
  • Improved Stock-Turnover Modeling
  • Improvements to the Integrated Benefits Calculator for modeling the health and agricultural impacts of air pollution.
  • Quality Improvements including built-in regression testing.
  • Usability improvements such as improved results visualization, better data editing, better importing/exporting, and support for multiple concurrent instances and multi-monitor support.

Latest Versions

By 2024, the number of users had reached 67,000 in 207 countries and economies. Highlights of the 2024 version of LEAP include:

  • Energy System Optimization Modeling: LEAP was previously limited to doing least-cost planning for a single sector (e.g., electric generation). The new version now supports full energy system optimization. In addition to optimizing the entire Transformation sector, LEAP can also optimize demand sectors specified using useful energy demands and model pipeline and transmission network expansion. These new capabilities are important for modeling deep decarbonization & net zero pathways. 
  • The LEAP Cloud Database Server (LCDS):  A system for connecting LEAP models to an internet-hosted database containing international open-source data covering energy, emissions, and development topics. The LCDS simplifies data collection and model maintenance - allowing users to easily update their models as new data becomes available. The initial version provided nationally-oriented statistics useful to energy modelers including UN population prospects, UN urbanization data, UN energy statistics, Word Bank development indicators, EDGAR emissions database, KAPSARC Cooling and Heating degree days, etc.  
  • Plugins: This version introduced a new plugin architecture that allows LEAP models to be created by quickly plugging together mini models that are developed and maintained by subject-matter experts. An online repository of plugins encourage experts to share plugins with the wider LEAP community. Plugins can contain contain standardized methodologies for modeling particular sectors or industries and can include suggested data structures and default data.  When used with the LCDS they can even include default data that varies by country. Plugins can be created in LEAP and easily shared as single data files.  
  • Energy Affordability: Examining the overall social costs and benefits of pathways is important, but even within broadly beneficial pathways it is important to think about how these will impact on different groups, and especially marginalized communities. This version of LEAP included a new type of analysis that helps users to study the affordability of pathways for different groups.  It includes the ability to specify detailed energy tariff structures including different block rates or tariffs that vary by the time of day.
  • Revamped User Interface: This version of LEAP features a revamped LEAP’s user interface that is more professional looking, more configurable, and easier and more enjoyable to use - while still being immediately recognizable for existing users. The revised interface includes updated icons and support for high-definition screens, better use of color, and support for multiple light and dark themes.  
  • Accessibility: Using Google machine translations combined with volunteer review, this version contains new translations in of the LEAP user interface (initially in 14 additional non-English languages) to make it more accessible to a broader audience including languages that are important in Africa and Asia – not just the standard UN languages. This new version also works with Google Translate to help users translate their models. Any model can be quickly switched between different languages providing more options for engagement among modelers and stakeholders.