This question is important to answer if we want to develop renewable energy for the future. Wind and solar energy are not always available around the clock, and these are the most powerful sources of renewable energy. Water power, bio-energy, and geothermic power can provide a continuous energy supply, but they cannot completely compensate for the discontinuity of wind power and solar energy. We need the ability to make wind and solar energy available at times when the wind is not blowing and the sun is not shining. For this, we have two possibilities:
- We can store the energy and use it when the wind is not blowing and the sun is not shining.
- We can build a worldwide smart grid and provide energy from regions where the wind is blowing and the sun is shining to regions that need that energy at a given time.
- We can use a combination of the two aforementioned possibilities.
A lot of possibilities are under investigation at the present time. When I visited the “Intersolar” in Munich in June of this year, I saw a lot of battery solutions, which increase the level of self-usage of sun energy for home owners. Trina Solar currently has a pilot project running in China to do the utmost with a smart grid. Many other storage developments are on the way.
A study was done in Germany which had the result, that with a smart grid, 30% of energy could be provided by renewable energy before having impact on the continuous energy supply.
Given all these observations, it seems that solution three, the combination of storage and a smart grid will serve as a guide to the future.
What are the roadblocks to this future and what still needs to be developed?
We need smart grids that include small energy producers and provide energy with high intelligence to the point of use. To achieve this goal, it is necessary to eliminate the interests of the present net providers and to put this task into independent hands to aim at the target to ensure the best possible energy distribution to meet all needs. The present energy suppliers have still too much interest to distribute the energy coming from their sources, which include coal and nuclear sources.
We need energy storage to ensure the continuous availability of energy if sun and wind energy are dominant. In my opinion, a combination of big centralized storage and individual storage will lead to success. Today, we have started to develop individual storage using lithium-ion batteries. This can be a solution. For centralized storage, in my opinion, we need pump storage and H2- storage. These storage solutions are not yet sufficiently developed. This action area is still open.
The last point, which is nearly a vision, is to connect all grids on earth to an international smart grid. At any given time, in one part of the world, the sun is shining and the wind is blowing. This region currently has too much energy available, so it can provide energy in places where it is nighttime or the wind is not blowing.
What do we really need? We need some individual storage, we need some centralized storage, and we need a worldwide smart grid. We can combine all of these with continuously available bio-energy, geothermic power, and ocean energy to ensure that basic needs are met. The rest will be managed by storage and a worldwide smart grid.