Global Energy Monitor

Accessible, asset-level dataset covering 183 countries harnesses satellite imagery and machine learning to support energy transition decision-making

Climate analytics non-profit TransitionZero today launched Solar Asset Mapper (TZ-SAM), an open-access global dataset of commercial- and utility-scale solar facilities utilising satellite imagery and machine learning. This is the first time that open-access, geo-located solar asset data has been made available at this level of granularity, and identifies small- and medium-sized solar assets at scale. Regularly updated, it can be integrated into system models for electricity grid operations and planning, supporting more effective forecasting by filling gaps in traditional methods of solar asset reporting.

Solar power is the fastest-growing power generation technology in history. In 2023 alone, the world added almost 400 gigawatts (GW) of solar capacity, equivalent to installing more than 192 football fields of solar panels every hour1. To effectively manage ongoing solar deployment, accurate and current facility-level data is essential. It enables the management of intermittency, facilitates grid planning, and allows for the assessment of trade-offs with biodiversity, conservation, and land protection priorities. 

Up to now, datasets of solar generating capacity have not been able to fully meet the changing needs of grid planners. Datasets are country-level, don’t adequately differentiate between large- and small-scale facilities, and struggle to keep up with the rapid pace of solar expansion. 

The TZ-SAM Q1 2024 dataset contains the location and shape of 63,616 assets, along with estimated capacities, an at least threefold increase in GW capacity for facilities under 5 MW compared to public and commercial alternatives. It estimates the construction date for over 80% of these assets. The dataset contains over 19,100 square kilometres of solar farms across 183 countries, with a total estimated capacity of 711 GW.

The dataset and methodology can be accessed now through Zenodo [DOI: 10.5281/zenodo.11368204] or through TransitionZero’s website.

Table: Comparison of Solar Generating Capacity DatasetsA

TZ-SAM85 GW (41,979)626 GW (21,637)11 GW (5,649)93 GW (2,447)11 GW (5,440)246 GW (6,706)32 GW (16,646)87 GW (5,566)
GEM122 GW (9,695)666 GW (12,612)7 GW (3120)72 GW (1831).004 GW (1)294 GW (4003)14 GW (6086)119 GW (2964)
S&P Global216 GW (7,594)308 GW (7,129)8 GW (4,160)95 GW (2,293)0.1 GW (57)39 GW (510)5 GW (2025)46 GW (1957)
IRENA31,419 GW139 GW610 GW272 GW
A. Figures in parentheses indicate the number of facilities in the dataset
1. Global Energy Monitor (2023), Global Solar Tracker. Figures presented in this table include all ‘certain’ and ‘uncertain’ facilities. Data from Luxembourg, Malta, and Slovenia are not present. TransitionZero is currently working with GEM to include TZ-SAM in future GEM Solar Tracker releases.
2. S&P Global Commodity Insights (2024), Global Clean Energy Technology. 6,491 solar assets do not have a capacity estimation and are excluded from analysis.
3. IRENA (2024) Renewable Capacity Statistics. IRENA provides aggregate country-level capacities only.

TransitionZero developed algorithms using earth observation and machine learning to accurately identify the capacity, land area, and age of every large solar facility worldwide, in addition to a large number of small and medium-sized assets. TZ-SAM’s methodology builds on  Kruitwagen, L., Story, K.T., Friedrich, J. et al. and uses the European Space Agency’s (ESA) Sentinel-2 dataset, combined with the community-driven and open-source OpenStreetMap (OSM) dataset for training labels. 

TransitionZero will host a webinar on Monday, June 24 at 12:30 pm BST to discuss this work. Register to attend here.

Matt Gray, Co-founder and CEO of TransitionZero:

To prevent poor decision-making resulting from ‘junk-in, junk-out’ modelling, utilising accurate and current geospatial data is essential. We’re excited to announce the availability of this innovative dataset and eagerly anticipate its integration into our software platform, Model Builder, later this year.

Diren Kocakuşak, Research Analyst, Global Energy Monitor: 

Keeping tabs on the global solar build-out requires all hands on deck. At Global Energy Monitor, we compile a project-by-project, ground-up inventory of solar installations for scientists, policymakers and the public. But as progress quickens towards the global goal of tripling renewables, providing complete and accurate data on the growing number of smaller-scale projects across the globe is increasingly difficult. TransitionZero’s Solar Asset Mapper addresses this challenge by rounding out the solar picture with geometries, locations, and capacity estimates.

TransitionZero will release regular updates to the TZ-SAM data set. Later this year, TZ-SAM will be integrated into Model Builder, a software platform that offers users an end-to-end service for capacity expansion and unit dispatch modelling. Sign up here to receive updates.

About TransitionZero

TransitionZero is a climate analytics non-profit established in 2021. We build accessible, auditable and open energy transition planning products, supporting mission-aligned organisations. For more information on how your organisation or initiative can access our data and analytics, visit our website or contact us.

About Global Energy Monitor

Global Energy Monitor (GEM) develops and shares information in support of the worldwide movement for clean energy. By studying the evolving international energy landscape, creating databases, reports, and interactive tools that enhance understanding, GEM seeks to build an open guide to the world’s energy system.


1. To calculate the area covered by 500 GW of solar PV in terms of football fields per hour over a year, we first estimated the area required for the solar PV by considering an average efficiency of 20% and using a conversion factor of 10 square metres per GW, resulting in 2.5 million square metres. Then, we determined the area of a football field (100 metres by 60 metres) to be 6,000 square metres. Dividing the total solar PV area by the area of a football field yielded approximately 416,667 football fields. Finally, we divided this number by the total hours in a year (8,760) to find that 500 GW of solar PV would cover an area equivalent to approximately 47.52 football fields per hour over the course of a year.