From Solar to Nuclear, Passing Through Wind and Biomass: An Analysis of Factors Affecting Costs and the Challenges in the Energy Transition Towards a More Sustainable Future

by Marco Arezio

The cost of electricity varies significantly depending on the energy sources used. Analyzing the available options reveals a clear difference in production costs per megawatt-hour, with sources ranging from renewables to fossil fuels and nuclear power.

To better understand the reasons for these variations, it is essential to examine not only the initial infrastructure costs but also operational costs, resource availability, and environmental impact factors.

Off-grid Solar Energy

Off-grid solar energy ranks among the most affordable options. This low cost can be explained by the ongoing reduction in the price of photovoltaic panels and energy storage technologies.

Despite the need for a considerable initial investment to purchase panels and batteries, subsequent operating costs are low.

However, it is essential to consider the variability in solar production, which is tied to weather conditions and daylight hours, often requiring expensive storage systems or connection to the grid during low production periods.

Geothermal Energy

Geothermal energy, which utilizes the earth's natural heat, offers a balance between low costs and stable production.

Unlike solar and wind energy, it is not subject to seasonal or meteorological variability, making it a reliable and predictable source.

However, the initial installation costs, particularly for accessing geothermal resources, can be high, limiting the spread of this technology to specific geographic areas with abundant thermal resources.

Onshore Wind Energy

Onshore wind energy represents one of the most cost-effective solutions for energy production. Onshore wind farms have benefited from a significant reduction in turbine costs and system efficiency.

However, their variability remains a challenge: wind energy is strongly influenced by geographic location and weather conditions. Areas with constant winds can ensure more economical production, but the need for wind farms to be near well-developed distribution networks affects overall costs.

Hydroelectric Energy

Although considered a renewable energy source, hydroelectric power has higher costs than solar, wind, and geothermal energy.

The reasons for this lie primarily in the infrastructure construction costs, such as dams and reservoirs, which require large initial investments.

Moreover, hydroelectric projects have a significant environmental impact, as they alter river ecosystems. However, once built, these plants can produce energy for decades with relatively low operating costs.

Advanced Nuclear Energy

Nuclear energy production, especially with advanced technologies, ranks among the more expensive options. This is mainly due to the high initial costs for constructing nuclear plants, which require a high level of security and sophisticated technologies.

The costs of managing radioactive waste and decommissioning plants at the end of their life cycle add significant expenses.

However, nuclear energy production is stable and not subject to the fluctuations that characterize renewable sources, making it an essential component for ensuring a continuous electricity supply in many countries.

Coal Energy

Despite the relatively high costs associated with coal, this energy source continues to be used on a large scale, especially in developing countries.

The costs include both coal extraction and combustion-related expenses, which produce large amounts of greenhouse gases and require emission treatment facilities.

Coal is often considered one of the most polluting sources, and many countries are working to reduce its use due to its environmental impact.

Biomass

Biomass, which uses organic materials for energy production, has one of the highest costs. Although it is a renewable source, operational costs — including the collection and transportation of biological materials— are significant.

Additionally, biomass energy production is not always as efficient as other renewable sources, and the environmental impact associated with combustion can be high, especially if adequate emission control technologies are not adopted.

Analysis of Electricity Costs by Energy Source

The chart illustrates the electricity costs per megawatt-hour (MWh) produced by various energy sources. This comparison highlights the broad variability in costs associated with different energy production technologies, ranging from renewable sources, such as solar and wind, to more traditional options, such as coal and advanced nuclear.

Let’s look at the details of each energy source represented in the chart.

Off-Grid Solar - $36.49/MWh

Off-grid solar energy stands out for its relatively low cost of $36.49 per megawatt-hour. This price results from the continuous reduction in the costs of solar panels and storage technologies, which allow energy to be stored and made available when the sun is not shining.

However, initial costs can still be high, but once installed, solar systems require low operating costs, contributing to a competitive price per MWh.

Geothermal - $39.82/MWh

With a cost of $39.82 per MWh, geothermal energy represents a reliable and stable energy solution characterized by relatively low operational costs once the necessary infrastructure is in place.

This type of energy harnesses underground heat, making it particularly effective and predictable, as it does not depend on variable weather conditions. However, installation costs are high, limiting this option to regions with abundant natural geothermal resources.

Onshore Wind - $40.23/MWh

Onshore wind energy has a cost of $40.23 per MWh, positioning it among the most economical renewable sources. Technological advancements have reduced turbine costs and improved efficiency, making this source competitive.

However, its production is influenced by wind variability and requires geographic areas with constant winds to maintain low costs. Despite these challenges, wind energy remains one of the most sustainable and economical sources for power generation.

Hydroelectric - $64.27/MWh

Hydroelectric energy, with a cost of $64.27 per MWh, is more expensive than the previously mentioned renewable sources. This increase is due to the high costs of building dams and water storage infrastructure, which require significant initial investments.

However, once completed, hydroelectric plants have a very long lifespan and generate energy at relatively low operating costs. Environmental impact, though, remains an important issue, as dams significantly alter local ecosystems.

Advanced Nuclear - $82.61/MWh

Advanced nuclear energy production costs $82.61 per MWh, positioning it among the more expensive sources. This is due to high initial construction costs, the need for advanced technologies to ensure safety, and the costs of managing radioactive waste.

Despite the high cost, nuclear energy provides stable production with no direct carbon emissions, contributing to the diversification of the energy mix and continuity of supply.

Coal - $88.24/MWh

At a cost of $88.24 per MWh, coal energy is still widely used, especially in developing countries.

While the cost of fuel and emission management expenses increase overall costs, coal is valued for its availability and reliability.

However, it is also one of the most polluting sources, emitting large amounts of greenhouse gases, which pushes many countries to reduce its use in favor of cleaner sources.

Biomass - $90.17/MWh

Biomass has the highest cost, amounting to $90.17 per MWh. This figure reflects the costs of collecting, transporting, and processing organic materials used to produce energy.

Although it is considered a renewable source, biomass efficiency is lower compared to other renewables, and the combustion process can have significant environmental impacts. To mitigate these impacts, advanced emission control technologies are required.

Conclusion

The cost differences among various energy sources are influenced by numerous factors, including installation costs, resource availability, production stability, and environmental impacts.

Renewable energies like solar and wind offer low-cost solutions but require support systems to ensure a constant supply.

In contrast, nuclear energy, though more expensive, provides continuous production with no direct carbon emissions.

The challenge for the future will be to find a balance between costs, environmental impacts, and supply stability, while ensuring a transition towards a more sustainable energy system.

© Reproduction Prohibited