How the world has sunk hundreds of billions of dollars in wind energy while barely reducing emissions

Significance 

The prime objective of the UN sustainable development goals (SDGs) is to achieve sustainable development in a balanced and integrated manner regarding the three key sustainability dimensions: environmental, social and economic. The energy sector, which is tied to SDG number 7: ensuring affordable, reliable and sustainable clean energy for all, is expected to contribute significantly. Clean and sustainable energy adoption is expected to drastically reduce the carbon footprint of the energy sector. To this end, different countries, especially developed economies, have invested significantly in various forms of clean energy, such as wind energy.

Whereas plenty of publications claim renewables can achieve sustainable development, there are many unanswered questions regarding their effectiveness in balancing the three dimensions of sustainability. For example, previous findings from the United States and German energy transition have produced contradicting results, revealing the difficulty of achieving a low-carbon grid. While the transition could reduce the emissions by a large percentage, the associated tradeoff effects on economic- and social dimensions of sustainability remain unresolved. Moreover, it is expensive, unreliable, and unaffordable in the long term. This warrants a thorough investigation into these issues.

Wind energy is one of the most important renewable energy sources owing to its broader geographical applicability. While it can nominally reduce emissions by 20 – 40% provided it is not puncturing peat and bogs, wind energy-related emissions have not fallen significantly. This leads to an unpopular question of whether wind energy reduces or increases climate gas emissions considering that it requires balancing power, which in most OECD countries is fossil. In addition, considering the entire system, wind might fail to reduce life cycle emissions, especially if it is greater than the displaced life-cycle emissions induced by wind, which is the case in most wind energy grids.

Herein, Professor Jan Emblemsvåg from the Norwegian University of Science and Technology investigated the sustainability of wind energy balanced by fossil energy. Specifically, the author tested the hypothesis that a wind energy grid balanced with gas power plants would reduce emissions than replacing the wind energy with the gas power plants in the same grid considering the life-cycle emissions. The model was constructed based on high-resolution grid data derived from the Irish grid which is ideal because it has the highest share of wind energy on an independent synchronous grid. The data covered four years and comprised the input from 828 Life-Cycle Assessment to enable detailed demand, supply and life-cycle emissions analysis. Monte Carlo simulations were used to sample the model 10000 times to improve result reliability. The work is currently published in the journal, Applied Energy.

According to Professor Emblemsvåg wind energy is renewable but not economically feasible towards low-carbon grids. Although wind energy reduced emissions by 10 – 20%, which supported the hypothesis, achieving a reliable and affordable low-carbon grid using current technology, emissions targets and costs are infeasible. Consequently, it is almost impossible for grid operators to accept high wind penetrations and expect to build affordable carbon grids. This would require higher alternative costs that may further compromise the system’s reliability. Moreover, this is more technically infeasible in smaller grids because the wind production is often too low regardless of the wind capacity installed and is mainly experienced when the balancing power is not based on fossil fuels.

Furthermore, it was worth noting that wind energy is highly dependent on balancing power, such that its emission impacts cannot be analyzed independently. These results are transferable to other grids with large penetration winds balanced using fossil energy – even the world’s largest grid, the European grid. The results contradicted the popular assumption that VREs are sustainable, which is incorrect because they are not independent energy sources as they fluctuate and require balancing. Their sustainability is therefore closely linked to the sustainability of their balancing power.

In summary, the impact of high wind penetration in grids with fossil balancing was analyzed through empirical data and simulations. Overall, the study concluded that wind energy, though renewable, is generally not sustainable when balanced by fossil-driven plants. Thus, it is important for policymakers to concentrate on what is sustainable and not what is renewable. In a statement to Advances in Engineering, Professor Jan Emblemsvåg provided more insights into the sustainability of wind energy which would contribute to improving the sustainability of wind energy and other renewable energy sources stating that “just because a power source has no direct emissions when used, it is the total, systemic life-cycle impact that counts, and because wind energy is not an independent source of energy it must be analyzed including balancing power and system reliability requirements. Over the last 20 years, humanity has reduced its share of fossil primary energy consumption by using wind and solar power by merely 3 percentage points after spending more than 2.5 trillion USD. This says it all”.

Reference

Emblemsvåg, J. (2022). Wind energy is not sustainable when balanced by fossil energyApplied Energy, 305, 117748.

Go To Applied Energy

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