The debate on renewable energy versus gas power generation is one that’s not going away anytime soon, and for good reasons.
As the world becomes increasingly aware of the impact of climate change, the energy sector has been forced to rethink its strategies. The pressure to reduce greenhouse gas emissions has resulted in a shift towards renewable energy. But where does that leave gas power generation? Let’s take a closer look.
First, let’s talk about the elephant in the room: the perception that gas power generation is dirty. According to the International Energy Agency (IAE), compared to coal, gas power generation is much cleaner. “That’s because it emits about half the carbon dioxide (CO2) and far fewer pollutants like sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter (PM),” says the agency.
It’s the classic “lesser of two evils” argument, but how tenable is itin the broader energy transition context?
“Despite being cleaner than coal, gas power generation is still a fossil fuel. It still contributes to climate change,” says Daniel Zywietz, founder and CEO of Dubai based renewable energy company, Enerwhere. “And in a world where we need to drastically reduce our emissions, we can’t keep relying on fossil fuels. We need to embrace renewable energy.”
Renewable energy has come a long way in recent years. Wind and solar power are now cost-competitive with traditional forms of energy. “Advances in technology have made renewable energy more efficient and reliable. It’s the cleanest form of energy we have,” says Prof. Tadhg O’Donovan, Professor and Deputy Vice Principal (Academic Leadership) Heriot-Watt University, Dubai.
So, which is better for the environment and the economy? It is a complicated question, and the answer depends on a variety of factors. Some argue that gas power is a necessary stepping stone towards a fully renewable energy future.
Gas power plants can be used to provide backup power during times of high demand or when renewable sources are unavailable. Plus, the advancements in gas turbine technology have made gas power plants more efficient and cleaner than ever before.
However, others argue that renewable energy is the only viable long-term solution to our energy needs. Renewable energy is becoming cheaper and more efficient every year, and the environmental benefits of transitioning away from fossil fuels are clear.
Plus, renewable energy can provide significant economic benefits, creating jobs and driving innovation in the energy sector.
“Technological advancements, including record-setting gas turbines efficiencies, upgrade solutions, hybrid systems and hydrogen-fuelled power generation offer a pathway to decarbonisation, while providing reliable, on-demand electricity,” says Joe Anis, President & CEO, Europe, Middle East & Africa, GE Gas Power.
“To address anticipated demand growth in the Middle East, gas, as a traditional source of electric power, will continue to play a vital role in dispatching flexible, resilient and lower emissions power.”
But, for the first time ever, 90% of all new power generation capacity globally is from renewable energy sources, an almost certain indication of how fast the energy landscape is evolving.
A record 295 gigawatts (GW) of renewable energy capacity was added across the world in 2022, up nearly 10% from the year before, according to figures by the Abu Dhabi-based International Renewable Energy Agency (IRENA).
“This continued record growth shows the resilience of renewable energy amid the lingering energy crisis,” says Francesco La Camera, IRENA’s director general.
“The strong business case of renewables, coupled with enabling policies, has sustained an upwards trend of their share in the global energy mix year on year.”
In Abu Dhabi, Emirates Water and Electricity Company (EWEC) has already met 80% of total power demand using renewable and clean energy from its solar and nuclear energy plants, supplying approximately 6.2 gigawatts (GW) of the total 7.7GW system power demand.
Worldwide investment in the green energy transition amounted to $1.1 trillion in 2022, setting a new record according to a report by BloombergNEF. It says this represents a rapid acceleration from the year before as the energy crisis prompted faster deployment of low-carbon technologies.
Saudi Arabia plans to invest up to $265 billion (SAR 1 trillion) to generate “cleaner energy”, according to the kingdom’s energy minister. Prince Abdulaziz bin Salman says the investments also aim to “add transport lines and distribution networks in order to eventually export the energy to the world and produce clean hydrogen”.
The UAE is already on course to add new solar capacity in the coming years. The 2GW Al Dhafra solar park in Abu Dhabi will soon be connected to the national grid, while the Mohammed Bin Rashid Al Maktoum Solar Park in Dubai has already reached 1.8GW capacity, with 950MW expected to be added soon, once Phase 4 is completed later this year.
While investments in solar and wind energy have gone up sharply, the same cannot be said for conventional thermal power generation sources such as gas, coal and oil.
Solar investment jumped 36% year-on-year to $308 billion and is estimated to have installed 260GW of new capacity in 2022, according to BloombergNEF. Investment in the second-largest sector, wind, stayed roughly stable at $175 billion.
China made up 55% of the world’s renewable energy investment, putting $164 billion into new solar farms and $109 billion into new wind farms. The US was the next largest single market, at nearly $50 billion. The European Union countries invested just $39 billion, down 10% from 2021 despite a strong rise in solar.
While there is an apparent increase in its dependence on renewable energy sources, the utilities sector still heavily relies on natural gas. This is projected to be an integral part of the power grid for several years or even decades to come, as evidenced by the ongoing energy crisis in Europe.
The utilities industry argues that they must continue using natural gas due to the unreliability of wind and solar power. Moreover, they are hesitant to invest in energy storage, as they believe purchasing batteries capable of powering the grid during periods of insufficient sunlight or wind would be too expensive.
“Gas-based power generation technologies provide a flexible option to swiftly ramp power output in response to fluctuations in energy supply caused by variable renewable sources, thus supporting grid stability,” says Noora Abdul Latif Kheily, Engineering Outage Planning Director for EMEA, GE Power.
According to Rajeev Singh, a Partner at EY, it will take decades to replace all of existing power plants with renewable energy sources, and even then, gas power will still play a role.
“The point is that while renewable energy is the future, it’s not quite the present. It’s not even the near future. Gas power is not the villain here, nor is it the hero. It’s a transitional fuel that will help us get from where we are now to where we want to be,” says Singh.
Some studies show that as a cleaner alternative to coal-fired power plants, the environmental impact of gas power can be further reduced through the use of carbon capture and storage (CCS) technology.
However, others argue that CCS is expensive and unproven, and that renewable energy is a better long-term solution to future energy needs.
While it is true that gas power can complement solar and wind energy to provide stability to the grid, Enewhere’s Zywietz argues that this is not the only solution available.
“Advances in energy storage technology, such as batteries and pumped hydro storage, can also provide grid stability and enable renewable energy to effectively provide baseload power,” Zywietz explains.
“Moreover, the argument that gas power is needed to provide baseload when the sun is not shining is increasingly becoming outdated. With the continued decline in the cost of renewable energy technologies, it is becoming more cost-effective to combine wind, solar, and storage technologies to provide a stable, reliable, and low-cost power supply around the clock.”
Other proponents of renewable energy have argued that the use of gas power as a backup to renewable energy sources may actually hinder the development of renewable energy technologies.
They claim that by relying on gas power as a backup, there may be less investment and incentive to develop and improve energy storage solutions, which could ultimately slow down the transition to a more sustainable and renewable energy system.
This brings us to the question of what role gas power will play in the future. Original equipment manufacturers (OEMs) for gas turbines such as GE, Siemens and Mitsubishi Power are constantly striving to increase the efficiency of their turbines.
GE’s HA gas turbine, for example, has an efficiency of 64%, while Siemens’ H-class turbine has an efficiency of up to 63%. Mitsubishi Power’s J-Series gas turbine, on the other hand, has a net efficiency of up to 64.1%.
To increase efficiency, OEMs are incorporating advanced technologies such as additive manufacturing, 3D printing, and digital twin simulations into their design and manufacturing processes.
They are also exploring innovative solutions such as using ceramic matrix composites (CMCs) for turbine blades and vanes to improve performance and reduce weight.
“These efforts are not only improving the efficiency of gas turbines and engines but also reducing emissions, enhancing flexibility, and increasing reliability, making them an important part of the transition to a more sustainable energy future,” says Alexander Eykerman, Energy Business Director Middle East & Managing Director, Wärtsilä Gulf.
Wärtsilä is one of a few established OEMS that have considered hydrogen combustion for gas turbines and engines as a promising alternative to fossil fuels due to its lower carbon footprint.
“One of the benefits of using hydrogen as a fuel is that it can be blended with natural gas to create a cleaner burning fuel. This can help improve the efficiency of gas turbines and engines, reducing their emissions and increasing their lifespan,” Eykerman points out.
Wärtsilä and WEC Energy Group recently successfully tested the capabilities of a Wärtsilä engine running on 25% hydrogen-blended fuel in what the group describes as a ‘key enabler’ for renewable energy ambitions.
GE is already enabling the transition of a 485MW combined-cycle power plant in Ohio, USA, to run on carbon-free hydrogen.
“If a power plant chose to blend 50% by volume of hydrogen into their hydrocarbon fuel, the carbon reduction can reach up to 23% at the exhaust. Implementing complimentary CCUS, the carbon reduction can be further reduced up to 90% or more,” says GE Power’s Kheily.
There are also advancements in gas-battery hybrid systems to help balance variable energy supply and demand, including when the sun sets and solar power production falls while electricity usage surges as people turn on lights and appliances.
Evidently, the push for renewable energy is stronger than ever, and there are valid reasons for that. However, as Anis argues, gas power is not going anywhere anytime soon. “In fact, as renewable energy installed capacity increases, gas power will play an even more important role,” says Anis.
Of course, there are those who believe that renewable energy will eventually fully replace gas power. And they may be right.
“But it’s not going to happen overnight,” says Singh. “We need to be realistic about the pace of change and recognise that we can’t simply flip a switch.”