2084 - When fossil fuels are history

DENMARK 2084

By Morten Andersen

The year is 2084. Wind turbines, wave machines, biofuel plants and fuel cells are the visible signs, but if you want to see the heart of the new energy system, you have to step into one of the computer centres.

Since all electric appliances are optimised with frequency electronics so their power consumption is minimal, consumption cannot possibly keep pace with all the electricity that is being produced. But the surplus energy is not wasted.

Even in the smallest towns, there are plants that make either hydrogen or liquid fuel. The technology is quite simple. The grid constantly knows how much electricity will be produced in the next five days – the weather reports and forecasts for wind, waves and sun are extremely accurate. So are the forecasts of the extent to which consumption will vary. Each time the grid calculates that there is plenty of electricity available, electrolysis is started up in water tanks which splits water into its two constituent elements, oxygen and hydrogen.

Illustration: Lars Chrois

Hydrogen, methanol and bioethanol

Some of the electrolysis plants produce only hydrogen. Most of the hydrogen is used in cars powered by fuel cells, or in the many fuel cell plants in people’s homes where they meet the needs for both heat and electricity. In addition, hydrogen is used in micro-fuel cells that run children’s toys and other small devices.

Other electrolysis plants are a bit more advanced. Instead of making pure hydrogen they make a mixture of hydrogen and carbon monoxide called synthesis gas. It is further processed to methanol, which most cars can run on. Liquid fuels for cars have the practical benefit of being easier to store and transport than hydrogen - as hydrogen is a gas at ordinary temperature and pressure. But hydrogen is inexpensive, so the fuel cell powered motor still has many loyal followers.

Many however prefer to fuel their cars with bioethanol. At the turn of the century, maize and other food crops were used to make bioethanol. But from 2020, this first generation bioethanol was superseded by the next generation, using enzymes to decompose straw, sugar beet tops and other forms of waste from agriculture and the production of food.

Bioethanol plants are usually co-located with electrolysis plants. Because when water is split water by means of electrolysis, not only hydrogen is generated, but also oxygen. And oxygen is necessary for making bioethanol. In the old days, oxygen was obtained by sucking it out of the air. But air is 80 per cent nitrogen, so a fair amount of the energy was wasted on pumping an unnecessary substance around. It is thus cheaper and more energy-friendly to exploit pure oxygen, which is an automatic by-product when water is electrolysed to make hydrogen.

US President Barack Obama praises Denmark as a model for renewable energy. Photo: Scanpix

Beautiful solar cells

In the first decades of the millennium, houses were still being built with small windows to save on energy. Here in 2084, it is considered optimally energy-efficient to use large windows. The window pane is provided with nano-perforation, which even on a winter day draws energy from the sunlight and is actually the principal energy source for providing electricity and heat in the home.

At the same time, glass has now become so strong that it is the preferred material of most architects. But houses cannot be built completely of glass, because there still needs to be space for solar cells. Previously, architects and industrial designers did everything they could to fit the cells as discreetly as possible into their products. They had been placed everywhere on buildings, vehicles and on all sorts of products without them being noticed at all.

That way of thinking is now considered old-fashioned. Instead it has become popular to exploit the decorative characteristics of solar cells, which sparkle strikingly in turquoise and deep blue shades.

Solar cells are now the principal means of producing electricity, closely followed by wind turbines – many of which are quite dated but are still steadily producing electricity – and the latest generation of attractively designed wave power machines.

Flexible consumption

On the consumption side, electric cars are the big energy users. But in some situations the electric car also functions as a supplier of electricity. Although there is an overall capacity
to produce a lot more electricity than is needed, situations can sometimes arise where there is a shortage of electricity e.g. when production from wind, wave and sunshine drops at a time when consumption is high.

When this situation occurs, electric cars can discharge electricity and restore the balance between consumption and production in the grid. Household appliances such as refrigerators, freezers and washing machines can also temporarily have their consumption constrained if electricity is likely to be in scarce supply. The same applies to machines in companies. Everything is managed by computer centres, which continuously communicate the price of electricity. Electric cars and many types of electric appliance can respond to price signals so that they serve their owner’s economy in the best possible way, and also in a way which ensures the overall balance of the grid.

There is still a lot of coal and oil in the world. But everybody agrees to let it stay where it is. Maybe it will be needed for something one day.

Illustration: Lars Chrois

Photo: Risø/DTU

In 2084 the energy system will be intelligent

 “It is certainly possible that we will more or less have freed ourselves of dependency on fossil fuels by 2084 – in our part of the world, that is,” says Henrik Bindslev, director of Risø DTU, the National Laboratory for Sustainable Energy..

“Should there be a surplus of energy in Denmark, as it is described, there will be a need for it in other regions of the world. If, at that time, there is plenty of electricity all over the world, it would surprise me.”

The Risø DTU director thinks it rather optimistic that the production and consumption of electricity in 2084 can be predicted exactly five days ahead, as it is described:

“On the other hand I am convinced that there will be intelligence built into all parts of the energy system. It will also be possible to postpone some of the consumption so that the balance in the energy system is maintained, and energy will be supplied back to the grid as it is described.”

Henrik Bindslev does not however believe that the range of fuels for cars will be as wide in 2084 as the article predicts:

“I think we will end up favouring either electric cars or hydrogen fuel cell cars. Most probably I think that it will be electric cars supplemented with synthetic liquid fuels, which could either be hydrocarbon or nitrogen-containing compounds, perhaps supplemented with biofuels for heavy goods road haulage and shipping.”

He doubts there will be surplus production of energy where liquid fuel is stored for longer periods:

“One has to remember that the new sustainable energy sources are more expensive than coal and oil. So general economic optimisation will see to it that no more energy is produced than necessary. But I can fully support the idea of oil staying in the ground. Oil is an amazing raw material for many purposes, so there are certainly better things to use it for than burning it!”