An exploratory research and resulting scenario about how far transformative changes on the energy end-use side can lead to.

The Low Energy Demand (LED) scenario study was a collaborative exploratory research carried out by several former IIASA Programs: Transitions to New Technologies Program (TNT), Energy Program (ENE), Air Quality & Greenhouse Gases Program (AIR), and Ecosystems Services and Management (ESM).

LED aims to illustrate how the historical trajectory of ever-rising energy demand leading to ever aggravating resource and environmental impacts can be reversed driven by technological, organizational and behavioral innovations in all aspects of energy end-use. Dramatic transformations in the way we move around, heat and cool our homes, and buy and use devices and appliances can help raise living standards in the Global South to meet, even exceed the UN Sustainable Development Goals, while also remaining within the 1.5°C target set by the 2015 Paris Agreement, and without relying on unproven and uncertain negative emissions technologies (CO2 removal from the atmosphere by technological means).

About LED

The LED scenario explores a pervasive transformation of the demand side of resource systems including food, energy, land, and water, as opposed to the more traditional scenario and modeling analysis, including Integrated Assessment Models (IAMs), which typically focus on resource provisioning or supply-side transformations. LED integrates a number of emerging trends centered around digitalization, device convergence, the sharing, and circular economy, and associated waste minimization strategies. New technological, organizational, and business model innovations, combined with behavioral changes revolutionize service provisions in direction of highest levels of resource efficiency.

The LED scenario consists of:

  • A rich scenario narrative sketching out how emergent trends could drastically change patterns of service provision and associated resource consumption.
  • A detailed bottom-up assessment of energy, food and water demands derived from LED scenario narrative incorporating also the concept of Decent Living Standards (DLS) for all.
  • A detailed model assisted assessment of supply-side implications of the drastic demand-side changes in the domains of energy, food, land, and water.
  • A model-based quantification of the climate and air quality impacts of the combined changes in resource use and supply.
  • An ex-post assessment of the SDG implications of the LED scenario for six SDGs.

In the modeling quantification of LED, the IIASA MESSAGE-GLOBIOM integrated assessment modeling framework was used, complemented by the MAGICC climate and GAINS air pollution and health impact models. Overall demographic and economic development trends as well as non-LED-specific scenario assumptions were based on the SSP2 scenario of the Shared Socioeconomic Pathways (SSP) framework.

Fast Facts

  • LED is one of the four illustrative model pathways in the IPCC Special Report on Global Warming of 1.5°C, and the only one without CCS
  • LED is the first scenario that quantifies the impacts of digitalization, sharing economy and behavioral change
  • LED is the lowest long-term global energy demand scenario ever published
  • The drastic transformative changes on the energy end-use side enable rapid decarbonization of the energy supply and near zero emissions by 2050, and demonstrates significant co-benefits for 6 SDGs

Results of LED

The research results are published in a peer-reviewed article in Nature Energy (Grubler et al. 2018) with ample supplementary information. Corresponding scenario quantifications for water are published in Parkinson et al. (2018).

The LED scenario data and results are documented in an online public database.

Key highlights of LED

Final energy demand can be drastically reduced by ca. 40% compared to the current level of energy demand (reference year 2020) by 2050.

According to the knowledge of the authors, LED is the lowest long-term global energy demand scenario ever published (245 EJ final energy demand globally by 2050).

At the same time, highly efficient systems of service provision enable an increasing convergence of living standards between the Global North and Global South, reducing global development inequalities, despite rises in population, income and activity.

The drastic reduction in energy demand can foster a rapid energy system transformation, pave the way towards swift electrification and the phasing out of fossil fuels, with reduced energy needs largely provided by renewables, and thus GHG emissions approaching zero globally be 2050.

The LED scenario meets the 1.5°C climate target without overshoot and keeps the global mean temperature increase below 1.5°C with a probability of more than 60%.

LED is the first scenario to show how the 1.5°C target can be reached without relying on unproven negative emissions technologies such as bioenergy with carbon capture and storage (CCS) which remove carbon dioxide from the atmosphere and permanently store it.

Significant co-benefits for a range of other sustainable development goals that generally outperform similar research findings are also demonstrated for LED including:

  • SDG2: the risk of hunger is reduced by increased food availability
  • SDG3: health is improved by reduced ambient air pollution
  • SDG7: The phase-out of traditional biomass use signals improved energy access to modern energy forms
  • SDG13: reduced temperature change positively impacts climate
  • SDG14: reduced CO2 concentration reduces ocean acidification
  • SDG15: less biomass use for energy and larger forest areas benefits biodiversity


The research is in part informed by discussions with demand-side researchers, for instance at the joint IIASA-RITE workshops (2018, 2019)