A Word with Cédric Philibert
2nd November 2017
Cédric Philibert, Senior Analyst in the Renewable Energy Division of the International Energy Agency
Using solar heat for industrial processes isn’t a new concept and with advancements in CSP technology, new opportunities are being presented. From aiding in the high temperature oil extraction process to low temperature food processing, the application of CSP in industry is providing unique opportunities and, of course, challenges. In this interview, Cédric Philibert of the IEA talks about CSP in industry and reveals these opportunities and barriers.
By Lila Neuberger
L.N. What areas of industrial application are starting to experience an impact?
C.P. So far, non-concentrating solar technologies have dominated industrial applications, with the bulk being in low temperature heat which is basically food and drink.
You can see CSP technology in sectors where you need higher temperature levels. There are several applications, mostly in industries such as food and drink, pharmaceuticals, and textiles.
You also have some in extractive industries. For example, the enhanced-oil-recovery (EOR) project by Glasspoint in Oman. They have adapted CSP to local conditions by using a greenhouse to protect the parabolic troughs from wind and sand. The greenhouse allows for a nightly roof cleaning and the use of lighter troughs. The steam produced is pumped into wells to extract larger quantities of oil.
Figure 1: Glasspoint’s EOR project in Oman
L.N. In what fields do you think CSP could have the biggest impact in terms of industrial applications?
C.P. There are two big areas: the extractive industries like oil, gas and mining and food processing. Both industries are usually remote, which drives up the cost of obtaining fuel and which usually means that they have available space for the installation of CSP troughs or towers.
However, the higher the temperature, the more difficult it is for solar to compete with fossil fuels. Efficiently reaching higher temperatures using CSP requires a more complex and well-built system, resulting in a higher cost. Furthermore, fuel is burnt at very high temperatures which means that burning fuel to meet low temperature demands is a bit of a waste, giving CSP more of an advantage in the low temperature range than in the high temperature range.
L.N. What are the main barriers for CSP in industrial applications?
C.P. Space is a barrier for sure. The others are cost and uncertainty. CSP has a different financing structure which requires all investments and costs upfront and you need 15-20 years to make a profit. However, mining companies are reluctant to sign a contract beyond five years because they only have visibility for the next few years (except for diamond mining) due to fluctuations in the market value of the commodities they produce. This makes it very difficult for them to get equipped with renewables which are only profitable if the industry or plant lasts 15-20 years.
PV developers have developed an offer of five years for the mining industry which is doable. The material is light enough that it can be reused in different places if the plant is closed, but this is difficult with CSP technologies. So yes, uncertainty over returns in volatile commodity markets is a real barrier.
L.N. How would you say these barriers can be overcome?
C.P. Space is probably the most difficult to overcome. We may see the relocation of industries over time to areas where you have good conditions, such as abundant sunshine and ample space.
Learning, economies of scale and moving to places where the resources and cost of capital are more favorable are very important dimensions in terms of overcoming the barrier of cost. Everything that can help de-risk the investment could lower the cost of capital and therefore reduce the total cost.
Additionally, governments can provide support to jump start the industry and reduce costs. France, for example, offers government funding to invest in process heat.
Lastly, an increase in the cost of burning fuels such as a carbon tax or an emissions trading scheme could help as well.
Figure 2: Temperature requirements by industry
Source: ECOHEATCOOL (IEE ALTENER Project)
L.N. You’ve mentioned that parabolic trough is one of the CSP technologies that is being used in industrial processes. What CSP technologies are best suited for industrial applications?
C.P. The best solar heat technology depends on what temperature is needed for a certain process. You have three different categories of temperature: low which is up to 150° C, medium-high which is between 150-500° C and high which is above 500° C. If you look at industry needs, you will have a big chunk of low temperature industrial processes are mostly done by flat plates or evacuated tubes. Troughs work very well for medium-high temperature needs. For temperatures above 500° C, which represents half the total need, you would use towers or ovens. It needs to be point-focus concentration to efficiently collect energy at high temperatures.
L.N In your professional opinion, what does the future hold for advancements of CSP and industrial application?
C.P. I see significant potential. Unlike space heating, which is difficult because of its inter-seasonal liabilities, industry has year-round energy needs and you make significant savings in the summer.
I see a future for CSP especially in medium temperature levels whereas it’s not yet economically viable for high temperature levels.