Expediting the introduction of renewable energy, smoothly phasing out fossil energy and – at the same time – saving energy, while ensuring that the energy supply remains secure, safe and affordable. This was the shared aspiration that prompted the Energy research Centre of the Netherlands (ECN) and TNO to join forces. ECN part of TNO has eight innovation programmes. Five questions and answers about ‘Towards an abundance of solar power’.
Progress towards the energy transition must be expedited if we are to meet the Paris climate targets. This requires technical, social and policy innovations. ECN part of TNO is taking up this challenge. Together with the Dutch business community, various research institutes and the government, it is implementing eight innovation programmes. Wim Sinke answers five questions about one of these programmes. Prof. Sinke is Principal Scientist Solar Energy at ECN part of TNO. He also holds the post of Professor of Photovoltaic Energy Conversion at the University of Amsterdam.
“Solar power systems are now twice as efficient as they were in the 1980s, and only one fiftieth the price”
1. What is the goal of the ‘Towards an abundance of solar power’ programme?
“Accounting for just under three per cent of the total, solar energy plays a modest part in the Netherlands’ electricity supply, and in the world at large. However, the growth figures are spectacular, so things are changing very rapidly indeed. This is being driven by spectacular reductions in costs and increases in yield. Solar power systems are now twice as efficient as they were in the 1980s, and just one fiftieth the price. These days, everyone is convinced that solar energy is going to be very big indeed. That is a real milestone in the history of this development. Accordingly, one of the main goals of this programme is to ensure that the ongoing growth process proceeds as quickly and effectively as possible, while maintaining public support.”
2. What does the programme involve?
“In an effort to cut costs even more dramatically, we are exploring every aspect of solar energy, from the materials used up to and including uses for complete systems. We are also working with our partners to develop power-generating building structures for roofs, facades and windows. This will enable us to harness solar energy on a much larger scale than we do today – by as much as a factor of fifty.”
“Take SolaRoad, the first bike path in the world capable of converting sunlight into electricity. The people behind it are now working on roads with built-in solar cells”
“But buildings are just one of the aspects we are working on. Our entire infrastructure has a surface area of many square kilometres which, in principle, could be used to combine the regular functions with solar power generation. In this way, solar energy could be exploited in all kinds of places. Take SolaRoad, for example, the first bike path in the world capable of converting sunlight into electricity. The people behind it are now working on roads surfaced with solar cells.”
3. What unusual challenges are waiting in the wings?
“Solar energy installations in open fields, in particular, are a hot topic. As an alternative to meadows filled with long rows of dark blue panels, we are exploring ways of varying the designs, materials and colours used and of combining functions. On the one hand, for example, we want to preserve nature conservation values and to cultivate agricultural crops. On the other hand, we want to generate solar power. By fully exploiting the capabilities of today’s new technologies and by making intensive efforts to improve them still further, we will create unprecedented freedom.”
“Another challenge is sustainability. Solar energy systems are designed for eternity, but this does have a downside – they are difficult to recycle. The trick is to combine a long service life and high reliability with sufficient scope to recycle and recover valuable materials.”
4. Which partners are involved in this programme?
“Various academic research groups play a very important part. Together with AMOLF (a research lab that is part of the Netherlands Organisation for Scientific Research), almost all Dutch universities are active in this area. They are focusing mainly on basic research into new materials, production processes or solar cells that may be used in the longer term. ECN part of TNO generally operates in the more applied areas and at higher technology readiness levels. This also involves the second major group of partners – the business community. It is worth noting that all three groups (the universities, ECN part of TNO, and the business community) often work together in projects. Last year, all of the PV research groups in the Netherlands joined forces to formulate a joint research plan. This plan combines basic and applied research in the area of solar energy into a single master plan.”
“Our society’s level of electricity electricity consumption is increasing sharply. We want to meet that growing need”
5. Will there come a time when the Netherlands has too much electricity?
“That’s not something that worries me, or rather: it is what we hope to achieve! The key concept behind an abundance of solar energy (and also of wind energy) is that the amount of electricity you produce exceeds your immediate needs. Our society’s level of electricity consumption is increasing sharply. We want to meet that growing need. At the same time, we feel it is important to help boost the sustainability of other forms of energy use as well. One way to do this is to convert electricity. It could be used to generate low temperature heat for buildings, as an alternative to the use of natural gas. Or to generate high temperature heat for industry. In the longer term, we will also convert electricity to fuel aircraft or shipping, or to bridge seasons.”
Tandem solar cells are an example of ‘hard core’ technological development. The type of tandem solar cell that has been most intensively studied has a bottom cell made of silicon, which is the specialty of the ECN part of TNO research group at Petten in the Netherlands. The top solar cell is a modified thin-film solar cell made of perovskite, a specialty of the Solliance consortium at Eindhoven. Stacking these cells produces a panel with an increased efficiency, extending an unbroken trend of growing panel yields over the past fifty years. Dutch Solar Design is an example of a completely new version of solar energy. The consortium behind this venture plans to market solar panels with a totally unexpected appearance. The first practical tests of attractive, electricity-generating building facades are planned for early 2019.