Energy is the bedrock of civilisation, so much so that the scale scientists will use to determine the sophistication of any alien civilisations we may one day encounter is based on their energy use. For most of human history, communities have relied on the energy of human and animal muscle. But since the industrial revolution, the world has tapped a different energy source – the power of the sun stored in the remains of organisms that died millions of years ago.
Fossil fuels changed everything. They have created unprecedented prosperity, brought the four corners of the globe within a 24-hour flight of each other, and transformed the way we produce food and a whole host of other products beyond the wildest dreams of our ancestors.
And energy from fossil fuels has allowed us to generate electricity, bringing the quiet revolution of light and refrigeration to our homes – not to mention smartphones, televisions, and a whole host of other gadgets. Or at least it has to most of the world. The number of people without access to electricity has fallen steadily – by an average of nine per cent per year between 2015 and 2019. Yet today, 770 million people still lack electricity, mostly in sub-Saharan Africa. The work of extending the life-changing benefits of electricity to everyone is therefore unfinished.
The issue of access to electricity and energy must be tackled alongside another existential challenge – the global energy transition. The burning of fossil fuels is heating up the planet’s climate—by at least 1.1 degrees Celsius already since pre-industrial times—causing a whole host of devastating impacts that are all too obvious to anyone following the news. The world as a whole must therefore transition away from fossil fuels towards affordable and clean energy – and fast. The role of innovation in what is arguably humanity’s greatest ever technical challenge is obvious. Yet the solutions innovators are finding are creative, and sometimes surprising.
New renewable energy sources
Today, the largest renewable energy sources are hydropower, wind, and solar. Wind and solar energy, in particular, are forecast to ramp up during the energy transition, and innovators are working to optimise these established sources incrementally. Wind turbines are becoming hardier, quieter, and more efficient, while solar panels are increasingly being integrated into the built environment in innovative ways – through walls, the facades of skyscrapers, and even blackout blinds.
But in addition to optimising solar and wind, innovators are also thinking outside the box about whole new energy sources. One company is using small turbines to turn almost any waterway into a power source, while another is seeking to harness the power of deep-sea currents. Even nuclear power, in use since the 1950s, is getting a makeover with seaborne nuclear plants that could act as mobile energy sources.
Energy storage
One of the key challenges we face as we move away from fossil fuels is how to store energy from variable sources. What do we do when the sun doesn’t shine and the wind doesn’t blow? Much of the focus has been on batteries, but these come with their own challenges – not least the demand they create for scarce materials that are extracted in environmentally damaging processes. Undeterred, innovators are working to create safer, greener, more efficient, and more affordable batteries, such as one developed in Germany that is made using globally abundant resources.
Batteries are far from the only game in town when it comes to energy storage, however. For example, a prototype system that stores energy in the form of heat and compressed air is 30-40 per cent cheaper than lithium-ion batteries. And another system stores energy on the ocean floor using a mechanism similar to a hydroelectric dam. Hydrogen, in particular, is considered a good candidate for energy storage, and two companies are exploring how hydrogen could be stored in underground shafts.
Energy efficiency
Target 7.3 within SDG 7 sets the goal of doubling the rate of improvement in energy efficiency, a reminder that we must look at energy demand as well as supply. There are many inefficiencies in homes around the world that lead to wasteful energy consumption. For example, in South Africa, a country that faces particular challenges with the security of the power supply, many homes use inefficient electric water heaters, known locally as ‘geysers’. One startup has developed an innovative device that reduces the impact of these systems by tailoring heating to user habits.
Another way in which energy efficiency can be improved is through new building materials that reduce the demand for energy-intensive heating and cooling systems. For example, engineers from China and Germany have developed a wood-based cooling foam that could reduce the cooling energy needs of a building by more than a third. Roofs and windows are another source of energy inefficiency. Researchers in Singapore have developed a window coating that blocks infrared but not visible light, while a smart roof coating developed in the US could also lead to energy savings.
Off-grid energy systems
Extending affordable energy to the remaining proportion of the population who lack it is particularly challenging. Many of these communities are remote, situated a long way from traditional energy infrastructure. Innovators have been responding with modular, portable energy systems.
For example, a Swiss company has developed fully autonomous solar-powered micro-grids that can be used and scaled up by almost anyone. The system is designed to be fully autonomous, and plug-and-play – allowing users to simply plug the system together with no configuration, specific know-how, or maintenance required. Another system developed by a company founded in Tanzania has developed a standalone ‘mini grid’ that draws on multiple energy inputs and a smart storage system to provide continuous power to off-grid communities across Africa.
Back-up generation
Energy systems need to be resilient as well as green and affordable. When natural disasters knock out the main energy grid, hospitals, data centres, and other essential services need to have access to backup supplies. Today, many backup generators still run on polluting diesel. To tackle this problem, one company has developed a generator that can run on a range of fuels, including ammonia and hydrogen.
And it’s not just hospitals that need backup power, so too do households, especially if they are situated in regions prone to supply disruptions. Grassroots NGO Deciwatt has developed a muscle-powered emergency generator for such vulnerable communities.
Words: Matthew Hempstead
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2nd August 2022