What is the Best Renewable Energy Source?

What is the best renewable energy source? As the world accelerates its shift toward sustainable energy, energy efficiency remains crucial in determining where to invest during the energy transition.

Efficient energy production is essential for maximising resource utilisation, reducing costs and achieving global decarbonisation goals. It allows us to identify the renewable technologies with the greatest impact and the least financial cost. This not only reduces how much new energy infrastructure needs to be constructed but also incentivises companies to invest in developing production capacity.

How Do We Measure the Efficiency of Renewable Energy?

Assessing the efficiency of renewable energy involves several key metrics.

Energy Return on Investment (EROI)

This measures the energy produced relative to the energy invested in creating the energy infrastructure. A higher EROI indicates a more efficient energy source. For instance, hydroelectric power often boasts an EROI of up to 250, while solar photovoltaic systems average around 6.

Capacity Factor

This represents a power plant’s actual output compared to its maximum potential output. A higher capacity factor means the plant produces energy more consistently. Wind turbines, for example, have an average capacity factor of around 33%, whereas geothermal plants can reach 70%.

Life-cycle Greenhouse Gas Emissions

Efficiency isn’t just about energy output; it’s also about environmental impact. Measuring the total greenhouse gas and carbon dioxide emissions over a system’s life cycle helps determine its net effect on greenhouse gas emissions.

What Is the Efficiency of Renewable Energy Sources?

Renewable energy sources vary widely in efficiency levels due to differences in technology maturity, resource availability and geographic factors.

What Type of Renewable Energy Is Most Efficient?

Hydroelectric power is considered the most efficient renewable energy source, with facilities often achieving efficiency rates of up to 90%. Their high EROI and capacity factor make them reliable. Countries like China have capitalised on this, with projects like the Three Gorges Dam generating around 111.8 billion kW/h in 2020.

What Type of Renewable Energy Is Least Efficient?

Certain biofuels have lower efficiency due to the energy-intensive processes required for cultivation and conversion. Their EROI can be as low as 1, making them less favourable than other renewables.

Is Renewable Energy More Efficient Than Non-renewable Energy?

Fossil fuels like coal and natural gas have much higher energy densities than renewables. While this has historically made them attractive, they are also a finite resource and generally have significant energy losses during conversion and transmission. For example, coal power plants have an average efficiency of about 33%. Furthermore, they contribute heavily to greenhouse gas emissions, creating substantial environmental and health costs.

On the other hand, renewables have a lower energy density but are far more efficient. Additionally, these technologies are generally less developed than non-renewable options, giving more room for efficiency improvements. For example, solar panels efficiency has increased by 40% over the last decade.

Another important consideration is that renewable sources offer long-term sustainability with lower environmental costs.

When factoring in externalities, renewables often surpass non-renewables in overall efficiency. For example, wind power and solar power have become cost-competitive with fossil fuels, even without subsidies.

How Can We Achieve Greater Energy Efficiency?

Improving energy efficiency in the renewable sector is crucial for maximising benefits and achieving sustainability goals. It requires a multifaceted approach that equally embraces technological advancements, supportive policies and collaboration.

At the core, it is critical to continue investing in R&D for renewables to support technological improvements and generate electricity. However, this alone is not enough. Renewables are largely intermittent energy sources, so improving grid infrastructure with smart grids and energy storage solutions can reduce losses and better balance supply and demand.

To support the investment required for these costly endeavours, governments must develop supportive policies for both the construction of renewable infrastructure and the necessary research. This can come from subsidies and incentives or carbon markets that push companies to increase renewable energy demand.

Lastly, regional collaboration is critical. Sharing resources and knowledge can lead to more efficient regional energy systems. For example, the ASEAN Plan of Action for Energy Cooperation aims to enhance energy security and sustainability in Asia.

What Is the Best Renewable Energy Source for the Future?

It’s impossible to crown a single type among different types of renewable energy sources as the best to generate energy. Each type can be the best based on local conditions. For example, while hydropower has high efficiency, it requires a river, which makes it difficult for areas without this type of water source on hand. Alternatively, solar energy is great for high-irradiance areas but is less ideal for areas with a lot of cloud cover.

The Best Renewable Energy Source for Asia

Looking at Asia as a case study for other regions around the world, several emerging technologies and trends could redefine its renewable energy landscape. Other regions are going through similar transitions and focusing on different technologies based on available resources.

Solar Energy

Solar energy is poised for significant growth, with declining costs to produce electricity and improving efficiency. Floating solar farms are an innovative solution, particularly in countries with limited land availability, such as Singapore. Solar power can be rapidly deployed for electricity generation at utility-scale, commercial and residential levels.

Wind Energy

Offshore wind farms are expanding across the region’s long coastlines. Recent technological improvements allow the development of offshore wind farms for generating wind power in deeper waters that were previously not financially and logistically feasible.

Asia has a developed offshore wind capacity of 30 GW. Experts predict this will reach 100 GW by 2030 and 2,600 GW by 2050. This will account for 60% of the world’s offshore wind capacity.

Hydropower

Asia has, by far, some of the most developed hydropower capacity. Many Asian countries include hydropower as a key player in their energy transitions and have plans to enhance existing hydro infrastructure and develop new facilities in the coming decades.

Tidal and Geothermal Energy – Emerging Technologies

Tidal and geothermal energy offer great potential due to Asia’s extensive coastlines and geothermal hotspots. Indonesia has the world’s most extensive geothermal resources, accounting for 40% of the world’s total potential capacity.

With this in mind, Asia’s best renewable energy source for the future will likely be a mix of solar and wind energy, complemented by hydro and emerging technologies.

Advancing Net-zero Goals Through Efficient Renewable Energy Development

In summary, assessing renewable energy sources using efficiency metrics like EROI and capacity factors is essential for making informed investment decisions. Renewable energy development is critical for achieving net-zero goals and global decarbonisation. By prioritising efficient technologies, we can accelerate the energy transition and meet sustainability targets essential for the future.