GEMdev: Grounded Energy Modelling for equitable urban planning development in the global South Grounded Energy Modelling for equitable urban planning in the global South (GEMDev) is a partnership between UCL (London), FCPV and PUCP (Lima) and CDRF-CEPT (Ahmedabad), which aims to create new knowledge to ground energy planning tools in the realities of everyday life and energy practices of off-grid communities.   Insecure and informal access to energy impacts on all aspects of life for poor communities living in sub-standard housing in the global South. Access to affordable, reliable and safe forms of energy services has particularly profound effects on health and economic opportunities. However, the ways in which these communities access and use energy in their day-to-day lives are poorly understood. The ways in which those practices change when informal settlements are upgraded or relocated are equally poorly understood.  As data-driven approaches to energy planning, such as Urban Building Energy Models (UBEMs), gain increasing importance as planning tools, this lack of understanding risks further marginalising the most vulnerable communities as their needs are either entirely overlooked or planned solutions fail to address their needs. UBEMs have been developed in, and widely applied to, cities in the global North to model urban energy consumption on a building by building basis, allowing the assessment of impacts of different energy conservation measures and policies. Such tools are highly attractive to energy planners in the global South, but the complexity of informal settlements is wholly absent from these models at present.    GEMDev will use participatory research methods to co-create datasets with marginalised communities to ensure that they are represented in the UBEMs of the future. Engaging these communities in the creation of the knowledge and datasets in order to represent them in energy planning tools is a highly novel approach which not only ensures meaningful recognition, but, through the research process itself, increases communities' capacity and skills, amplifying their voice in the planning processes that have profound impacts on their lives.  Lima and Ahmedabad have been selected as the cases for application of the GEMDev project for both methodological and practical reasons. From a methodological perspective, both are global cities characterised by significant inequalities in access to energy and other services but with very different histories of development and policies for addressing the needs of the urban poor. From a practical perspective, we will build on strong existing research partnerships in both cities. The UCL/FCPV partnership in Lima contributes expertise in participatory methods and strong engagement with municipal authorities, while capacity in building energy modelling will be built through an innovative approach between private and public universities, PUCP and UNI. The UCL/CDRF-CEPT partnership in Ahmedabad contributes expertise in energy modelling and the project will build capacity in participatory methods. The strong focus on South-South knowledge transfer is a key example of the equitable partnerships which underpin this project.  GEMDev will deliver a robust, co-produced evidence base on energy practices, use of space and urban form in Lima and Ahmedabad. This will be used to not only support the local development of UBEMs for these cities, but also to co-create alternative archetypes of the off-grid city. These findings can inform city, national and regional policies that support the delivery of multiple Sustainable Development Goals (SDG), including SDG7 on energy, SDG11 on sustainable cities and communities, and beyond. The inclusion of partners and stakeholders in developing this proposal will help to ensure the project delivers real and long-lasting change for marginalised, off-grid communities in the global South. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.