The biggest misconceptions about batteries, hydrogen and CCS

Should we invest in batteries or hydrogen? Can carbon capture save heavy industry? And why not simply store all our surplus wind power in batteries?

The debate about the green transition can quickly start to sound like a competition between technologies. But asking which technology is best only makes sense if the technologies are actually trying to solve the same problem.

Batteries, hydrogen and CCS are a great example. They can all play an important role in the transition of the energy and industrial sectors, but their functions, strengths and limitations differ.

What the technologies do have in common is that they are often credited with capabilities they do not have, or judged on tasks they were never designed to perform. This has given rise to some persistent misconceptions about what batteries, hydrogen and CCS can and cannot do.

Here are five of the most common misconceptions.

Misconception 1: Batteries can solve all energy storage needs

Batteries have an important characteristic in an energy system with large amounts of wind and solar power: they can respond quickly.

When electricity generation and consumption are out of sync, batteries can absorb electricity and supply it back to the grid later. In this way, they can help balance the electricity grid and shift electricity from periods of high generation to periods of greater demand.

In the electricity system, batteries are particularly well suited to providing short-term flexibility. For example, the International Energy Agency IEA, highlights that battery storage can be well suited to providing flexibility over periods of 1–8 hours. At the same time, batteries can respond within seconds, making them useful for supporting grid stability.

But that does not mean batteries are automatically the best solution for every type of storage. The greater the amount of energy that needs to be stored and the longer it needs to be stored, the more important factors such as capacity, material use, space and cost become.

In other words, batteries are not the answer to every energy storage need, even though they are already a key technology for certain types of flexibility in the electricity system.

Misconception 2: Hydrogen is a general replacement for fossil fuels

Hydrogen is often described as one of the green fuels of the future. But it can be misleading to think of hydrogen as an energy source in the same way as, for example, wind and solar power.

Hydrogen is primarily an energy carrier and an industrial feedstock. It can, for example, be produced through electrolysis, where electricity is used to split water.

Today, global demand for hydrogen remains concentrated in traditional applications in industry and refining. At the same time, the IEA points out that low-emissions hydrogen could play an important role in sectors where emissions are difficult to reduce and other solutions are unavailable or difficult to implement, including parts of heavy industry and long-distance transport.

That does not mean hydrogen should replace fossil fuels everywhere.

Instead, the technology is particularly relevant where its specific properties can solve a problem that is difficult to address in other ways.

And that is precisely why it does not make sense to see hydrogen as a universal competitor to technologies such as batteries. The two technologies can play different roles in the energy system.

Misconception 3: CCS means we can carry on as before

CCS stands for Carbon Capture and Storage, meaning the capture and permanent storage of CO₂.

The technology can be used to capture CO₂ from sources such as industrial facilities. The CO₂ is then transported to a location where it can be permanently stored in suitable geological formations.

This can give the impression that CCS allows us to continue emitting CO₂ and simply clean up afterwards.

But it is not that simple.

CCS requires both energy and infrastructure for capture, transport and storage. And capturing CO₂ does not in itself make a production process climate-neutral.

However, some industrial processes generate emissions that do not come solely from the energy used in production.

Cement production is a classic example. CO₂ is released as part of the chemical process when limestone is converted into clinker. Even if the energy supply for the process were changed, these process emissions would therefore remain. This is one reason why carbon capture is highlighted as an important option for reducing some of the industrial emissions that are difficult to avoid.

CCS is therefore not a substitute for energy efficiency, electrification or other emission reductions.

Instead, it is another tool for tackling emissions that are difficult to eliminate in other ways.

Misconception 4: Batteries, hydrogen and CCS are competing to do the same job

This is perhaps the most important misconception.

Imagine an energy system with large amounts of wind and solar power.

When electricity generation temporarily exceeds demand, a battery can store the electricity and supply it back to the grid later.

Electricity can also be used to produce hydrogen, which can be used as an industrial feedstock, among other applications, or as a basis for producing other fuels and products.

At an industrial facility where the production process itself generates CO₂, CCS may instead be relevant for capturing some of the CO₂ that would otherwise end up in the atmosphere.

These are three different tasks.

So asking which of the three technologies is best quickly becomes misleading. A more relevant question is: What problem are we trying to solve?

Misconception 5: One technology will emerge as the clear winner

Technology debates have a tendency to look for winners.

Batteries versus hydrogen. Electrification versus Power-to-X. Carbon capture versus renewable energy.

But the energy system already consists of a wide range of technologies, forms of energy and infrastructure that need to work together. And the more energy we produce from sources such as wind and solar, the more important the interaction between generation, consumption, storage, transport and industry becomes.

Batteries can provide rapid flexibility in the electricity system. Direct electrification can be efficient where it is technically feasible. Hydrogen can play a role in certain industrial applications and other areas where its particular properties are valuable. And CCS can be relevant for some industrial emissions that are difficult to eliminate in other ways.

The green transition is therefore unlikely to be won by any single technology. Instead, the challenge will be to choose the right technologies for the right problems and make them work together.