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Clean energy technologies – the state of play


The need for clean energy technology has never been more important. The way we currently produce and consume energy is unsustainable, and while technology is not the only ingredient to a cleaner energy future, there is no credible path to net-zero emissions without a significant and speedy ramping up of clean energy technologies across the entire energy sector.

The carbon footprint of the global energy system has been reduced in waves driven by government policies. For instance, construction of nuclear reactors surged in the 1960s and 1970s, but slowed down thereafter. More recently wind and solar PV have seen rapid expansion, led by policy support in Europe, United States, the People’s Republic of China (“China” hereafter) and India. The expansion of wind power is evidenced since the late 1990s and today accounts for over 5% of global power supply. Solar PV expansion was not too far behind and now accounts for about 2.5% of global power supply. Biofuels for transport has expanded steadily to reach 3% of global transport energy requirements today, mainly due to blending mandates and production targets in Brazil, United States and European Union.

Global primary energy demand by fuel, 1925-2019


Clean energy technology progress, however, has been slow in end-use sectors. Energy efficiency has been the main means of moderating growth in CO2 emissions in end-use sectors. Some progress has been made, notably in the development of electric cars, which accounted for 2.6% of global sales in 2019. The momentum for critical technologies such as hydrogen and CCUS is also increasing. If the world is to reach net-zero emissions this century, faster progress will be needed in end-use sectors, which accounted for 55% of energy and industry-related CO2 emissions in 2019.

Progress in deployment of clean energy technologies has been outpaced by overall energy demand growth. In 2019, CO2 emissions from fossil fuel combustion reached more than 33 gigatonnes (Gt), a record high. Many existing energy assets are still young, particularly in Asia. Around 45% of installed fossil-fuelled power generation capacity in Southeast Asia was built within the last ten years, and 70% within the last 20 years. Much of the infrastructure for the production of steel, cement and chemicals is also relatively young, particularly in China. The global average age is 10-15 years, compared with a typical lifetime of 30 years for chemical plants and 40 years for steel and cement plants. Existing energy infrastructure could lead to nearly 750 GtCO2 of additional emissions by 2070 if unchanged. This would exhaust the majority of the remaining CO2 budget compatible with limiting the global temperature rise to ”well below 2°C”, let alone 1.5°C as set out in the Paris Agreement. 

Age profile of global production capacity for the steel sector (blast furnaces and DRI furnaces)


Age profile of global production capacity for the chemicals sector (ammonia, methanol and HVC production)


Age profile of global production capacity for the cement sector (kilns)