The global challenge of reducing climate change requires a transition to a low carbon economy (IPCC), and the ambitions of the international community, formalized in the Paris Agreement, gives opportunity to bottom-up initiatives to realize this goal. We see great progress in decarbonizing electricity, increasing energy efficiency, and developing grids for renewable energy sources. While [...]

The global challenge of reducing climate change requires a transition to a low carbon economy (IPCC), and the ambitions of the international community, formalized in the Paris Agreement, gives opportunity to bottom-up initiatives to realize this goal. We see great progress in decarbonizing electricity, increasing energy efficiency, and developing grids for renewable energy sources.

While these developments contribute to a sustainable economy, other unsustainable practices remain. One of the key challenges that is receiving little attention is the demand for heating and cooling, which is to a great extent supplied by burning fossil fuels. Half of the energy consumed globally (IEA, 2012) is for heating and cooling purposes, which means that clean thermal energy innovations alternatives will contribute largely to global CO2 reduction

Figure 1. Primary energy for heating and cooling in the EU (EU source)

Solar heating technologies offer a clean alternative that can replace fossil fuel usage, and thereby reduce CO2 emissions. These technologies collect thermal energy from the sun and use this heat for drying purposes, for the heating and cooling of buildings or to provide process heat. Advanced technologies can provide temperatures of up to 400 °C, potentially fulfilling almost 50% of heat demand in the industrial sector (IRENA). To harvest the solar thermal potential, advanced innovations are needed.

Industry potential

The International Energy Agency (IEA) describes that solar thermal can fulfill a substantial amount of heat demand within any given country and irrespective of the geographical location. In developed economies, solar thermal can provide technically about half of this energy consumption by supplying hot water and steam. In emerging economies, especially in those where agriculture, the textile, brick and food processing industries are important sub-sectors, solar thermal energy can provide the hot air and hot water needs. Solar thermal technology can also provide an alternative to cooling processes in sectors where most product cooling is currently done by electric chillers.

Solar thermal technology already allows for lower temperature industrial processes and application in buildings (see table 1), making it an interesting clean energy source for industries like food, beverages, paper, hospitality and textiles, where a high percentage of the heat demand is in the low temperature range. Solar heating can already be applied for processes like washing, sterilizing, drying, bleaching and dying in these industries. In the food industry for example, solar heating is already being applied for larger industrial scale drying processes. However, to fully utilize the potential of solar thermal energy, more advanced solar thermal technologies that can cope with higher-temperature heat processes are required.

Table 1. Key figures for Solar Heat for Industrial Processes. (IEA & IRENA, 2015).

Challenges for wider deployment of solar heating technologies

While solar thermal plants have great technological potential challenges for upscaling the deployment of solar thermal plants remain. Key challenges are the lacking economic competitiveness of current technologies, the complexity to integrate solar thermal plants into existing industry processes. Furthermore, data on energy prices and incentives are not easily accessible, making investment decisions and policy decision-making difficult.

The deployment relies heavily on the economic competitiveness of the innovations. Solar thermal installations have high investment costs, while operating costs are practically zero. Payback times of more than eight years are high compared to conventional installations with payback times of less than five years, which makes investments in solar thermal plants unattractive at this point. However, increased deployment, and larger-scale applications will lead to further cost reductions of the technology. For this, greater specialization and the ability to succeed in a broad range of applications is needed. In the end, solar thermal innovations do have the strength of reducing operational costs and create independence of volatile fossil fuel prices.

Besides the economic competitiveness, the integration of new heat sources into existing industrial processes remains complex. To start with, the industrial complex need to have sufficient rooftop space for installing the solar thermal panels. Additionally, solar thermal solutions need to be tailor-made for specific industry demands and be accompanied by heating storage solutions. The implementation of solar thermal as an energy source for industry requires innovations that deal with the integration complexity.

Finally, there is a strong need for accurate data on energy prices, local energy taxes, and incentive schemes to promote renewable energy sources. While detailed data on energy statistics are available, the reliability is arguable and the accessibility is limited. This issue, especially present in emerging economies, makes it difficult for companies to do a detailed cost-benefit analysis.

The availability of data is also important for the development of policy instruments. Current government incentives to increase clean energy technology competitiveness have little focus on solar thermal heat, or are still in its infancy. The existing instruments have little effect on lowering the payback times, and therefore do not increase the economic competitiveness of solar thermal installations. And where policy for solar heat exists, it usually focuses on residential heat, missing the opportunity for industrial applications of solar thermal technologies.

Innovating towards a solar thermal future

To overcome the current barriers that withhold us from utilizing the solar thermal potential, additional innovations are needed by different actors. There is a strong need for integrated solutions that are tailor-made for different sector’s needs.

Integrated solutions

To meet market demand, integrated solutions are required. Innovators can make their solutions more attractive by addressing complex, diverse energy demands. For example, by combining solar thermal panels with conventional solar PV panels for electricity, electricity and thermal energy can be generated at the same time, serving both electric and thermal energy demands. Innovators could further specialize their solar thermal technology into specific temperatures combined with the heat storage solutions. These innovations should be ready to be implemented for large-scale industrial processes.

Tailor-made plug-and-play solutions

To implement solar thermal technology for industries, applications need to be tailor-made for different sector’s needs. The food and beverages, textiles, paper and hospitality industries all have different energy demands, but the technology is suitable to serve these industries, meaning that standardization is possible. By standardizing the technology, cost-efficiency rises and the possibility for plug-and-play solutions emerges. These plug-and-play technology solutions can then be applied at smaller-scaled installations, which is particularly interesting for emerging economies. Eventually, these plug-and-play solutions can lead to quick implementation, upscaling the large-scale deployment.

Solar thermal partnerships

Solar thermal technology is ready to be implemented on a larger scale. To upscale the deployment, and overcome the barriers alliances should be formed. These alliances should include partnerships between industry players to share business demand, solar thermal tech-companies to bring the innovations needed, and policymakers to create a level-playing-field. The alliances can tackle the complexity issues of solar thermal applications, improving the technology’s competitiveness. Furthermore, knowledge and data sharing between the partners can take place, which will lead to industry specific analyses and improved decision-making for investing, and directions for policy-making. Data on life cycle benefits, both economic and environmental, can be generated by different stakeholders, including energy-users and governmental actors. The partnerships and knowledge-sharing should ultimately lead to a best practices platform, where data, solutions and applications can be showcased.

Altogether, the advanced solar thermal solutions and alliances can advocate the potential of solar thermal technologies to policymakers. Government incentives play a key role in making solar thermal technologies competitive. With solar thermal technology, they can achieve their sustainability target, while reducing the costs of energy for consumers and industries. While governments should advocate the benefits of solar heating for industry more, the alliances can help to push this agenda. By showcasing the best practices, a bottom-up push can be created to put solar thermal innovations higher on the agenda.

Authors: Utku Kucukosmanoglu en Koen Groot.