Energy and Meteorology Portal

Energy Transition

To limit global warming to well below 2°C compared to pre-industrial levels, 196 countries signed the Paris Agreement in 2015, a legally binding international treaty on climate change. Recognizing that rising temperatures and the consequential changes in weather patterns, increment of extreme events and ice melting leading to sea level rise are linked to greenhouse gas emissions (IPCC 6th  Assessment, 2022, Figure 1).  

Figure 1. Correlation between CO2 ppm and global temperatures, and dates of international initiatives to tackle climate change. Source: Sustentio, adapted by @ProfMarkMaslin

To achieve the stabilization of global warming while fulfilling the Sustainable Development Goals (SDG), the world needs to:

  1. Drastically reduce CO2 emissions and other greenhouse gases (Paris Agreement, UN 2015b).
  2. Drastically increase the renewable energy uptake (IEA, 2022 and COP28, 2023).
  3. Drastically increase energy efficiency (SDG 7.3, UN 2015a, and COP28, 2023).
  4. Stop ecosystems and soil degradation, and land-use change. Degraded ecosystems reduce the capacity of the planet to buffer changes (EU, 2009).
  5. Drastically reduce consumption and wasteful use of resources in general (SDG12, UN 2015a), as they require energy to be produced (Ivanova et al 2016).

In addition, measures need to be taken to mitigate the effects of global warming.

The energy sector alone is currently responsible for about 70% of carbon emissions. As the world moves towards decarbonization, aiming to achieve net zero emissions by 2050, in line with the 2015 Paris Agreement, it is imperative that society makes a significant shift in the way energy is produced and consumed (IEA 2021).

To inform this shift, the International Energy Agency (IEA) published a flagship report in March 2021, with a roadmap for reaching net zero by 2050 in the global energy sector, requiring almost 70% of global electricity to be generated through solar and wind power by 2050. In addition, a massive effort to electrify the transport and heating sectors is needed (IEA 2021).

Energy systems are the engine of economic and social development, essential for the functioning of the other sectors: agriculture and food security, water, health and risk reduction (all these are priority areas, including energy, of the Global Framework for Climate Services, GFCS). Energy generation and planning of operations are markedly affected by meteorological events, and energy systems are increasingly exposed to weather volatility and climate variability, affecting both the electricity supply and demand. By utilizing advanced weather and climate information, energy systems can therefore considerably improve their resilience to weather extremes, climate variability and change, as well as their full chain of operations during their entire life cycle.

Under the current efforts to reduce GHGs, addressing climate change will require a transformation of the entire energy sector, where the share of renewable energy in the energy mix of countries is expected to increase dramatically (IEA 2021). However, as it can be seen by comparing the two maps in Figure 2, there is still a long road ahead given the current relatively low base of renewable energy uptake and use. Overall, electricity plays a leading role in the energy transition. By 2030, the world needs to triple the global renewable power capacity and double the energy efficiency (COP28, 2023). Electricity generation from renewable energy sources and energy efficiency measures can achieve 90% of the required carbon reduction if target measures and commitments occur as planned. Although there have been important additions to renewable energy, it currently meets just over 11% of total demand – a merely ~2% increase from a decade ago (IEA, 2022).

Figure 2. Comparison of global electricity production from renewables and fossil fuels in 2020. Source: Our World in Data.

Meanwhile, 2021 was the year with the highest carbon emissions ever, with a 20% increase in energy demand compared to the last decade (IEA, 2022): this was partly due to the increase in economic activity to make up for the slow down during the peak of the COVID pandemic, in 2020.  Given the limited time available to halt the causes of climate change, a drastic and fast-paced structural shift from fossil fuels to renewables is required in all societal and economic activities. There is no time for a gradual transition. REN21 suggests that Renewable Energy Share is the appropriate measure to monitor this transition (Figure 3).

Figure 3. The estimated renewable share of Total Final Energy Consumption for 2009 and 2019. Source: REN21 based on IEA data.

To make this index closer to 100 % renewables, a suite of tools is needed to support the transition, including clear targets, policies and investment, with timely and reliable information supporting energy efficiency, energy resilience and energy access. The information provided by Weather and Climate Services is key in this structural shift (WMO No. 1301, 2022).

Along with a structural shift, a reliable and resilient energy supply needs to be guaranteed, and a huge increase in flexibility and responsivity of the electricity system is required. As the grids transit to hybrid smart grids, the development, knowledge sharing, capacity building and implementation of key elements is essential: data, information technology, smart technology, weather readiness assessments, adequacy assessments, policy frameworks, infrastructure regulations and guidelines, market instruments.

Particularly critical would be for developing countries – some with a population still lacking energy access – to leapfrog technological development and build their hybrid smart grids with state-of-the-art knowledge, technology, and policies. To this end, developing general guidelines, standards, and regulations is essential, as well as sharing knowledge and technology, By doing so, advances and developments can more easily spread across countries, thus increasing the speed of the energy transition and at the same time reducing inefficiencies.

Weather and Climate Services and Energy Transition

Weather and Climate Services (W&CSs) provide essential information for all elements of the energy supply chain and help the transition towards renewables, by informing:

  • Resource Assessments. Identifying new locations for renewable power plants and safe locations for long-term system expansion. New power plants need to have a positive return on investment for their lifespan. To evaluate this, potential generation needs to be calculated considering weather variability and climate change.
  • Long-term investments. Informing projects for grid development and new power plants, as they need to consider the potential future impacts of climate change. Multi-decadal and longer climate projections showing possible evolution of climate considering different emission scenarios are well needed for planning purposes.
  • Weather-Readiness Assessments. These assessments are key for ensuring that existing energy systems are fitted for expected weather variations; under this category there are also Adequacy Assessments of energy systems, aimed to ensure energy generation can meet demand over the upcoming years while also managing a renewable energy mix.
  • System efficiency. Timely and reliable weather nowcasting and forecasting services are required to improve system efficiency by ensuring supply meets the forecasted demand.
  • Power grid management. Weather nowcasting and forecasting services, that combine (near) real-time observations with numerical models (including machine learning ones), support renewable plant operations and grid management.
  • Food-Energy-Water Nexus Climate information from seasonal forecasting and projections can provide key information which help design management strategies and planning that go beyond the energy sector alone, accounting for sectors such as agriculture and water, through for instance a balanced use of water resources for hydropower and other uses.
  • Strengthening collaboration within the energy sector. W&CSs are most useful when co-designed with users: interactions and collaborations with developers, producers, operators and managers open the arena for innovative solutions for weather and climate products, in areas such as hybrid grid management and energy efficiency.


According to REN21 the energy transition towards renewables has been slowed down by pernicious obstacles:

  • Lack of integrated, cross-sectoral strategies to drive the transition
  • Lack of sufficient policy support and enforcement
  • Persistent support for fossil fuels and low economic support for renewables (Figure 4)
  • Lack of concrete measures to decarbonise economies
  • The need for infrastructure development and increased affordability in some markets
  • The need for more innovation in some sectors.

Figure 4. Energy investments in COVID-19 recovery packages of 31 countries, showing preferential investment in fossil fuels. Source: REN21 with data from