Geothermal and biofuels represent a combination of energy sources that are essential in the transition towards a more sustainable and environmentally friendly global energy system. Geothermal energy harnesses heat from the Earth's core, converting it into usable electricity with minimal greenhouse gas emissions. On the other hand, biofuels are derived from organic materials such as plant biomass, agricultural residues, and even algae. These energy sources collectively contribute to the diversification of the energy mix and help reduce dependency on fossil fuels, which have been the primary contributors to climate change and environmental degradation.

Electricity generation from geothermal and biofuels involves distinct processes. Geothermal power plants utilize the Earth's heat by tapping into underground reservoirs of steam and hot water, turning turbines that drive generators to produce electricity. Similarly, biofuels are used to generate electricity either by direct combustion to produce heat, which is then used to turn steam turbines, or through biogas in combustion engines. This blend of geothermal and biofuels offers a versatile and decentralized approach to electricity generation, contributing to energy security and grid stability.

One of the significant advantages of utilizing geothermal and biofuels is their relatively low carbon intensity compared to traditional fossil fuels. With carbon intensities ranging from 38 gCO2eq/kWh for geothermal to 230 gCO2eq/kWh for biofuels, they are significantly cleaner than coal, which stands at 820 gCO2eq/kWh. This makes geothermal and biofuels a compelling choice when considering the large carbon footprint of conventional power generation. Although geothermal-and-biofuels electricity production is still a developing sector, it holds immense potential as part of a broader strategy to reduce emissions globally.

Even though geothermal and biofuels contribute a relatively small percentage to the current global electricity portfolio—significantly less than 5%—certain regions see more substantial utilization. For instance, in Sri Lanka, 1% of electricity is generated from geothermal and biofuels, while in Sub-Saharan Africa, this figure stands at 2%. These numbers, though modest, indicate the growing role of diverse low-carbon technologies in meeting regional energy needs and helping to alleviate energy poverty.

Equally deserving of attention are other low-carbon energy sources like wind, nuclear, and solar. Wind power, with its low carbon intensity of 11 gCO2eq/kWh, is capturing strong global interest. Nuclear power, always a reliable and steady source of clean electricity, has the smallest carbon footprint at just 12 gCO2eq/kWh. Solar power is pivotal as well, offering remarkable potential with its carbon intensity of 45 gCO2eq/kWh. Together, these technologies represent a robust foundation for the expansive growth of electricity that is both sustainable and environmentally responsible, while also addressing air pollution and climate change. Expanding these low-carbon technologies is crucial for a secure, clean energy future.