The future won’t just be about saving energy – it will be about looking at clever ways to reuse energy that would otherwise be wasted.

Not only will we need to find new sources of energy, we also need to find inventive ways to reuse it.

In the future, wasting energy will be unthinkable – and although this is good news, it won’t be enough to tackle the issues of increased energy demand and an ever-growing population. So, we will need to turn our attention to recapturing and reusing energy as well.

Massive amounts of energy are being lost when we heat homes, businesses and other buildings; the world over, energy wastage such as this is happening on a huge scale. And this needs to change if we’re to slow climate change and create a future with a sustainable energy system.

In the UK alone, more than half of the energy produced is wasted, right at the source. Some 54 per cent of heat energy generated at power plants escapes before it can be turned into useful electricity, according to a report by the Association for Decentralised Energy.

This wasted energy is worth £9.5bn per year. Per person, that’s equivalent to more than half the average UK annual electricity bill – about £592.

A great deal of heat energy is lost in homes and buildings that are not energy efficient as well.

This is why the 2012 Energy Efficiency Directive requires all new homes in the EU to have nearly zero-energy building (NZEB) status by 2020, and all new public buildings to be NZEBs by 2018.

According to UK energy saving advice website, TheGreenAge, 35 per cent of heat energy is lost in the home through the walls and gaps in and around windows and doors, 25 per cent is lost through the roof, and another 10 per cent is lost through the floor.

Insulation, sealing gaps, switching to more efficient modern boiler systems, and installing double glazed windows are obvious ways of reducing this kind of home energy wastage.

Another, often overlooked problem is water heat wastage. Around 15-30 per cent of a typical home energy bill is spent on heating water, while almost 90 per cent of the energy used to heat shower water is wasted.

This inspired me to design Zypho, a water heat recovery device that’s installed under a shower tray or bathtub to capture and reuse around 10°C of lost heat energy that would otherwise go down the drain.

This energy is then reused to heat the cold water travelling to the shower tap, cutting carbon footprints and reducing energy bills by up to 30 per cent.

Energy recovery is also occurring in different forms, and on a larger scale. For example, in the Swedish capital, the Stockholm Data Parks project is harvesting heat energy generated from the masses of computers in its data centres to heat 900,000 homes in the city.

The cold water used to cool the air in data centres to stop servers from overheating is, in turn, heated-up itself. But rather than wasting this now-hot water, it is distributed back to a cooling and heating agency and redistributed for heating homes.

These two example, Zypho and Stockholm Data Parks, illustrate how a combination of small scale units and large industrial scale projects can help us get more from the energy we are currently using. In the future, this heat recovery will be the key to reducing our energy use.

New and unlikely ways to generate energy

As well as reusing wasted energy, pioneers are also looking at using energy from some unlikely sources.

For instance, Belgian company Turbulent is pioneering whirlpool turbines, which harvest river or canal water to provide low-cost energy to small rural communities, 24 hours a day.

A solar panel being developed at China’s Soochow University that can generate electricity from falling raindrops will give solar panels another way to harness natural energy.

It’s even possible to harvest piezoelectric energy – electricity generated by the use of pressure – as the Institute of Physics (IoP) explains.

One example involves using the force required to press a button to charge small, low-power electronic devices, thus replacing the need for batteries.This would also cut down the use of batteries, which are already complicated to dispose of as they contain chemicals and metals that are harmful to the environment, and to humans.

On a larger scale, piezoelectric floor tiles could harvest “the kinetic energy generated by the footsteps of crowds to power ticket gates and display systems”. One company making this a reality is Pavegen, which has installed smart floors and pavements in a number of locations.

As well as harvesting otherwise wasted energy, we will also see a shift towards the reuse of waste itself.

Marcus Gover, director at the UK advocacy group WRAP, told the Guardian that by 2025, waste disposers “won’t be burying or burning people’s rubbish as they do today”, they will instead be returning “valuable resources to manufacturers”.

One solution, the Guardian highlights, “is turning waste into energy” – a market predicted to be worth $37.64bn by 2020.

The article also references US biotech firm LanzaTech “that uses patented microbes to convert carbon-rich waste into biofuel via a gas fermentation technology” and Novozymes, a Danish biotech firm that uses “an enzyme-based solution that converts used cooking oil or other lower grade oils into biodiesel”.

Energy and the Internet of Things

Deveci Tech’s Enlil vertical axis wind turbine is another innovative invention. By installing it at roadsides, Enlil is able to capture the wind energy of passing vehicles, as well as natural winds.

What’s arguably even more impressive, is its use of smart measuring, which is made possible by the Internet of Things (IoT) – a network that allows physical devices to connect and exchange data.

The device is also able to take measurements such as temperature, carbon dioxide and humidity levels, and could potentially even be used as an earthquake monitoring system. All this data can also be viewed on a mobile app.

By connecting devices to the IoT, we’re able to use the masses of data available to streamline how they operate. In terms of energy efficiency, the potential is massive.

Visability is the key to energy efficiency, according to Gerd Kortuem, a professor of ubiquitous computing at the Open University and energy leader for Milton Keynes’ smart city initiative.

The IoT “ultimately creates much more visibility: the visibility of the performance of the grid, visibility of where we lose energy, and where the savings potential really is,” Kortuem told the Guardian.

By being able to see where the most energy is lost in any given appliance or process, we’re then able to work towards recapturing and reusing that energy, or indeed reduce any unnecessary energy at the source.

IoT-powered smart grids, “allow energy distribution to be managed in real time based on immediate data rather than historic patterns of energy use”, the Guardian explained.

Twinned with smart meters, they are able to reduce the energy bills, energy efficiency and ultimately the carbon footprints of businesses.

We can also expect the IoT to be used to create ‘smart cities’ that would maximise efficiency in everything from waste management to traffic congestion.

The next stage will involve artificial intelligence (AI) managing and maintaining our IoT-powered devices, processing data in real time and quantifying how to use it to streamline every process.

For instance, Siemens is already using AI to manage and maintain gas turbines. This is not just a case of AI imitating the work of humans – it is able to improve upon human labour and thinking immensely.

With the ability to process massive amounts of data, AI is able to analyse the individual components of machinery – which reduces the need for servicing – operation and environmental conditions.

As the years go on, we can expect the IoT and AI to be applied to all forms of energy use and reuse, and this is sure to make our lives far easier while minimising the impact on our environment, and our wallets.

The road to a greener future

All around the world, solutions are being tried and tested to create a greener and more energy efficient future.

So whether solutions are considered on large, city-wide scales, in the context of small communities, or even within each individual home and building, the first pioneers are crafting new energy efficient solutions, as well as promoting a whole new way of thinking.

These steps may seem small and insignificant on their own, but by implementing many small steps at once, we can recapture and reuse a huge amount of energy that would otherwise be wasted, and left to heat our atmosphere.

And if we’re to truly overcome the future energy challenges fuelled by overpopulation and climate change, this new mindset will be key to solving them.

So whether we’re able to make a difference on a small scale in our own lives, or look for solutions that can be applied the world over, the responsibility of promoting energy efficiency and reuse belongs to all of us.

With so many innovative solutions already available the world over, I’m confident that we’ll see some truly radical changes in the way we view, use and reuse energy a lot sooner than you might think.

José Melico is founder of Zypho