If we flew round the world from Hiroshima to Fukushima, we would pass over thousands of sites contaminated by radioactive material. Some are places we’ve all heard about, power plants that melted down catastrophically like Chernobyl and Three Mile Island or famous nuclear testing sites like Los Alamos National Laboratory or Pokhran, India. Other sites are less while known and are likely to have been used for storing radioactive materials. All, however, are testaments to the dangers that nuclear power and nuclear weapons pose.

A sustainable future is one without nuclear weapons and nuclear power, but as countries transition from non-renewable sources of energy, like nuclear and coal power, to renewable sources, they are faced with a significant challenge. Wind and solar power depend on natural resources that are only intermittently available.

Where will electricity come from when the sun is not shining and the wind is not blowing?

Some countries, like Germany, keep non-renewable sources of energy on the back burner. When power grids are starved for electricity clouds and stagnant air, they switch on coal and natural gas power plants to meet demand.

Sparing using of non-renewable energy is much more sustainable than complete reliance, but it falls short of building a sustainable power grid. Even limited use of coal and gas power plants can contribute to global climate change.

Scientists and engineers need to find ways to store renewable energy so that it can be available when the sun and wind are not. The good news is that there is no shortage of good ideas.

Tesla, the world-renowned electric car manufacturer, launched a line of batteries with enough storage capacity to power an entire home. Engineers designed the batteries to charge while the sun is out and during off-peak periods of the day when electricity prices are low. Tesla is not the first company to design a home-based battery for storing solar power, but they did kick up a cloud of excitement in the possibility of a future powered by renewable energy. Their battery is uniquely styled, lightweight, and compact. It’s perfect for the environmentally conscious consumer with some extra cash lying around to invest in sustainability (the batteries cost $3,000 dollars).

People without a padded bank account would benefit more from energy storage solutions with large scale applications.

In Norway, engineers are trying to develop a way to store surplus power hydraulically. Norway generates almost all of its electricity using 937 hydroelectric plants. They use gravity to turn generators propelled by water traveling through pipes. Norwegian engineers argue that these plants can also be used as gigantic batteries. Surplus power produced by renewable sources could be used to pump water from below a hydroelectric plant back into the lake the feeds it. During periods of low renewable energy output, Norway’s hydroelectric plants could be activated to supply power to parts of Europe that currently would switch on non-renewable energy sources.

Norway’s power plants first need to be connected to the rest of Europe’s. This is not a daunting task, since it is already common for many European countries to share energy when electricity supplies are both high and low.

The more difficult problem is finding a way to make Norway’s hydroelectric power instant. Norway’s rock hills are filled with tunnels that carry water to its hydroelectric plants, many of which can be several kilometer’s long. The length prohibits immediate power generation because it takes time for water to travel through the pipes and build up enough pressure to turn the turbines.

A promising graduate student named Kaspar Vereide argues that power plants can use “surge chambers” to solve this problem. Surge chambers are imbedded in the rock near a hydroelectric plant, and they use compressed air to pressurize water that flows into the tank. This means that the water flowing into the tank could immediately obtain enough pressure to turn hydroelectric turbines, and the surge chambers could operate until the water in the underground pipes acquired enough pressure from gravity to turn the turbines on its own.

No one has built Vereide’s model. If it is to work, there are major kinks that will need to be worked out, but Vereide is thinking in the right direction.

We need more thinkers that want to develop innovations that will make large-scale renewable energy systems a reality. We can wean ourselves from dangerous non-renewable sources of energy, like nuclear and coal power.

With the help of ideas like Vereide’s, we will.