In this Perspective, Gerhard Salge, Chief Technology Officer at Hitachi ABB Power Grids, explains why electricity will be the crux of a carbon-neutral energy system. He argues that electrifying the globe can only work with a much more flexible and interconnected power system, enabled by the right conditions.
Electricity has improved our standards of living since its invention more than two hundred years ago. But the changes that deepen electrification in the name of sustainability will bring over the coming 30 years will go beyond anything that we’ve seen so far. Analysis comparing and contrasting multiple recent studies of the evolution of the total world energy system shows that global electricity consumption will more than double from 20 percent (today) to over 40 percent of total energy demand by 2050. And certain regions of the world will go far beyond this level of electrification.
Three building blocks are stacking up to deliver this carbon-neutral electric future: connecting larger volumes of wind, solar and hydro to the grids; electrifying the world’s transportation, building and industrial sectors; and, where direct electrification is either not efficient or impossible, introducing complementary and sustainable energy carriers, such as green hydrogen.
Combined, these blocks will give us the foundation upon which electricity will become the backbone of the entire energy system and on which sustainable societies can progress.
The most efficient, cleanest and cost-effective way to electrify the world is to build renewable energy capacity and to harness energy from wind, sunshine and water that nature provides in unlimited reserves. As a result, we estimate that global renewable energy capacity will grow by at least a factor of ten until 2050.
Challenges: overcoming complexity and expanding the world’s grids
Electrification, powered by this huge growth in variable renewable power generation, brings a host of new challenges – but two stand out most to me: tackling the complexity arising from a greater number of widely distributed and less predictable power generation sites; and the need to significantly upgrade and expand grid capacity to accommodate the rapid growth in demand.
In order to manage fluctuating electricity production and new consumption patterns, our energy system needs to become more flexible and new tools are required to deliver this. Innovative grid components using power electronics will provide the operational flexibility needed to enable grids to become more efficient. Sensors will provide the necessary information and digital solutions will process the huge amount of information in intelligent grid control centres. This will enable faster decision making in a much more dynamic environment than we have ever seen in the past.
The second challenge, expanding grid capacity, can be tackled in two ways: optimising the utilisation of current networks and upgrading and extending power systems. Here, we can rely on clever combinations of power electronics and digital technologies to optimize copper and iron efficiencies on existing power grids. A recent example of this can be seen in Scotland, where a new HVDC link is being added to connect the Shetland Islands to the UK transmission system. (see QR CODE). The link will enhance security of power supply and help to transmit wind power generated on the islands, contributing to the UK’s decarbonization target of bringing all greenhouse gas emissions to net zero by 2050.
Grid capacity will need to cope with more than twice the electrical energy of today. This includes the expansion of high-voltage networks and interconnections across regions, linking renewable energy generated in remote places, such as wind farms located kilometres offshore, to the grid. In the future, one could even imagine the ability to harvest the Arctic winds.
From a demand-side perspective, this huge expansion will enable electrification to significantly rise in areas that have so far been low load regions – away from densely populated cities where demand is high. For example, through electrification it will become easier to locate a growing number of data centres in secluded areas. And we can expect to see more industrial sites, such as steel plants and mining operations, turn to electrification in a move to convert away from carbon-intensive processes whilst simultaneously, increasing efficiency.
Over the next thirty years, we are likely to see power systems also growing into geographical areas that, up to now, have rarely been taken into account in grid expansion planning.
Flexibility, storage and the role of complementary energy carriers
The journey towards a carbon-neutral energy system is dependent upon future power systems that are extremely flexible. They will need to cope with increased complexity, brought about by the need to integrate bulk and distributed variable power generated from renewable sources.
Whenever grid flexibility is required, the first and most proven technical solution is grid expansion and interconnection. Once this reaches its limit, energy storage starts to play an important role on the pathway towards a carbon-neutral energy system. Battery storage for electricity has already made impressive strides over the past years. With the rise of variable renewable power production comes a greater need for short-term electricity storage to ensure reliability of the power system. Battery technology is on its way to becoming the dominant solution for meeting short-term needs. It offers the highest flexibility and the most attractive cost-benefit ratio.
The buffers used in today’s energy system to deal with the variations of electricity production are, next to renewable hydro-electric power, mainly fossil-based energy carriers such as oil, gas and coal. These types of emission-intensive elements of the energy system will need to be phased out in a carbon-neutral world fit for the future.
Where direct electrification is not possible or cannot be achieved, complementary energy supply is needed. The studies highlight the role of hydrogen as a technology that is gathering pace. When planning for seasonal storage needs, tapping the potential of hydrogen is likely to play an important role. However, for this to be sustainable, we are talking about green hydrogen – produced from renewable energy sources.
Green hydrogen could also be a facilitator in lowering the carbon-intensity of sectors that cannot easily be directly electrified, for example, certain elements of the transportation sector (e.g. airplanes and large ships). This takes us back to my main point of electricity being the backbone of our future energy system, as green hydrogen is produced using electricity.
When planning and designing the future energy market, an important aspect that decision-makers should consider is not to overly rely upon one direction only. Power system expansion and interconnection offers opportunities to link time zones and even climatic zones instantaneously. Nevertheless, the future energy system needs both interconnections and energy storage. It should never be a question of building one or the other – because they are complementary.
Creating the optimum climate for trust, collaboration and the right investment
Time is of the essence in the move towards a carbon-neutral energy system. There have been several welcome policy announcements and initiatives of late, setting ambitious targets for a carbon-neutral future.
This includes the stimulus initiatives and goals to accelerate the European Union’s Green Deal, goals put forward by several countries including the UK, Japan, China and South Korea.
While this is laudable, it is imperative that planning and execution cycles are accelerated to unlock the necessary investments in our energy infrastructure. Policymakers need to set a clear agenda and enable this to happen, which includes putting in place the right regulatory framework and ensuring a degree of collaboration in key areas such as grid codes and market mechanisms. The area of interconnected electricity networks is also becoming increasingly important in order to maximise the penetration of renewables. Collaboration will clearly be a key success factor.
Be it Arctic winds powering electric vehicles to desert-harvested solar power feeding air conditioning systems, a carbon-neutral energy system will reshape the world. The challenge is so big that there is no room for picking winners – we need all sustainable solutions, current and future. We should not waste our energy and time on arguing about which is the better option, but instead focus on building sustainable partnerships, because only then will we accelerate and make an impact.
Building a global, interconnected and truly sustainable energy system for today’s and future generations with the help of fascinating technologies will bring unbelievable value for sustainable societies. This is what makes me proud and excited to be part of bringing such a vision to fruition.
