核聚变——替代化石燃料
随着全球能源需求与日俱增，创造可持续和可再生能源变得越来越重要。为了解决这个问题，研究人员正试图利用核聚变，将太阳产生能量的过程复制到地球上。
在本次采访中，贺利氏科纳米光学元件全球销售经理Frank Nürnberg博士介绍了用核聚变能替代化石燃料的重要意义。产生核聚变能有两种方法，其中一种需要使用高能激光器来实现核聚变反应。目前的实验可以达到约70%的质能转换率，也就是说约有70%的原料被转换为能量。
贺利氏专为高能激光器打造的合成石英玻璃为此做出了重要贡献。不同于传统的窗玻璃，合成石英玻璃在高能激光器所运行的波长范围内也能有效地传输激光束。
Read the interview: Transcript of interview with Dr. Frank Nürnberg
It's the dream of every scientist to bring the process of the sun to the earth.
Why is fusion energy the energy of the future?
The World Energy Council has predicted a required electricity factor of 1.5 in 40 years. Roughly 50 percent of that required energy will be generated out of renewable energy sources. However, the remaining 50 percent still require fossil production processes. Fusion energy is an alternative to that.
How does nuclear fusion work?
For nuclear fusion the hydrogen isotopes deuterium and tritium are fused under high pressure and high temperature conditions. This generates helium and a lot of energy, which then will be transformed into electricity.
As far as the input material deuterium goes – we have plenty of that due to the fact that we can use the ocean water to make it. Then focusing on the resulting product – helium – it’s a gas which we all obviously know is not a radioactive product coming out of a production nor generating a lot of CO2. As an easy example, the energy equivalent for 11 tons of coal is one gram of deuterium and tritium. With a yearly demand for a fusion factory of 250 kilograms, you see immediately that we have enough water in our oceans to provide here the resources for.
Why is a high-power laser needed to produce fusion energy?
There are two approaches for fusion right now. One is magnetic fusion, where magnetic fields are used to reach these conditions, and the other one is laser induced fusion. Lasers are perfect to deliver in a very short time period a lot of energy, which you need to start the fusion process.
How long will it take until fusion energy can be commercialized?
From the first thoughts of laser fusion to the first really successful experiment in 2021, we are talking about 70 years. That's a long period. We are currently reaching up to efficiencies around 70 percent. So that means that 70 percent of the energy is produced compared to what is put in the beginning on.
The start-ups we are in contact with right now are aiming to prepare the first demonstrator showing how we can go from a science research experiment into commercial energy production.
How is Heraeus contributing to fusion energy with its fused silica?
Laser systems used for fusion are operating in a wavelength range where normal glass is not transmissive anymore. This means you need a high purity glass. Fused silica has the ability to transmit the light in the required regions. In addition, it guarantees the lowest absorption. So, you would like to have all lights going through the optical element. In addition, you need hundreds of these optical elements for a system like that, and you need to guarantee the quality of every single piece and to be a reliable supplier here for these optical elements. And this is exactly what Heraeus can do.
