The integration of renewable energy sources like solar, wind, hydroelectric, geothermal and biomass into existing energy infrastructure presents many opportunities but also challenges that must be addressed for a successful transition. Some of the key factors involved in effectively integrating renewables on a global scale include developing supporting policies and regulations, upgrading transmission and distribution networks, employing energy storage and demand response techniques, and promoting renewable technologies appropriate for different regions and markets.
On the policy front, governments around the world need to implement policies that incentivize investment in renewable energy and help bring costs down through economies of scale. Feed-in tariffs that provide long term price guarantees for renewable power have been successful in many countries. Renewable portfolio standards requiring electricity suppliers to obtain a minimum percentage of power from renewable sources have also propelled growth. Carbon pricing regimes like emissions trading systems further level the playing field by making fossil fuels more expensive. Coordination between governments on consistent policy goals will help global renewable markets reach critical mass more quickly.
Countries will also need to invest heavily in modernizing aging electric grids to accommodate higher levels of variable wind and solar power. Two-way “smart grids” capable of monitoring power flows in real time and rerouting electricity where it is needed most will be critical. Long-distance, high-voltage transmission lines will be required to interconnect renewable energy zones with major population centers and enable balancing of supply and demand over wider areas. Microgrids that integrate distributed energy sources like rooftop solar with battery storage can make the grid more resilient. Digital technologies like blockchain could help facilitate transparent, trusted transactions among more decentralized grid participants.
The intermittent nature of many renewable technologies like solar PV and wind requires solutions for when the sun isn’t shining or the wind isn’t blowing. Large-scale energy storage using methods such as pumped hydroelectric, compressed air, batteries and power-to-gas can buffer intermittent supply. Demand response programs that incentivize reducing consumption during peaks can help balance the grid more cost effectively than “curtailing” renewable production. Time-of-use electricity pricing for consumers and industry encourages shifting usage to times of higher renewable output. Regional coordination of renewable energy zones and transmission can take advantage of geographical and temporal diversity effects between different resources.
A diversified mix of renewable technologies appropriate for each area’s resources should be pursued globally. For example, solar-rich regions like much of Africa and the Middle East could leverage significant PV potential. Off-shore and on-shore wind development makes sense in windy coastal areas and plains. Hydroelectric potential remains largely untapped in many developing nations. Geothermal power is well suited for the ring of fire around the Pacific Ocean. Biomass energy like from agricultural and forest residues plays a role where sustainable feedstocks are available. Emerging technologies like ocean wave and tidal power also show promise in appropriate locations. Off-grid and mini-grid renewable solutions can accelerate energy access in remote areas uneconomical for extension of centralized grids.
With supportive policies, sufficient capacity building, education and technology transfer over time, developing countries have a significant opportunity to leapfrog dirty energy paths pursued by industrialized nations. While up-front capital costs are challenging, renewables’ lack of fuel costs offers long term energy security and price stability to emerging economies. Public-private partnerships involving multilateral development banks can help address financing barriers. International collaboration between governments, private industries, civil society and international organizations will be pivotal for the global energy transition to succeed in a just and equitable manner.
While integrating high shares of intermittent renewables presents significant electricity network operational complexities, multiple studies confirm technical solutions exist within current technology means. With focused global efforts on the policy, financial, technical and capacity dimensions discussed here, renewable energy sources could realistically meet the vast majority of growing world energy demand in the coming decades while significantly curbing greenhouse gas emissions. Strong commitments from both developed and developing nations to align short term economic interests with longer term sustainability imperatives are paramount for the planet’s climate future. By pursuing a global integration of renewable energy in a cooperative international framework, countries have an opportunity to provide universal access to clean power and build a more prosperous as well as climate-resilient world for all.