Solar Heat For Industrial Processes
May 23, 2019
Solar energy is witnessing new technological advancements everyday. Now a new revolution is just around the corner. Now solar energy isn’t just for electricity. It can also provide carbon-free heat for a variety of industrial process. The industrial process that drives our economy – manufacturing, food production, mining, chemical production is always under the hood. But there is one common point which drives these industries – Heat, a lot’s of it, which takes an enormous amount of fuel to produce it. Heat and fuel is an important part of any industrial economy. But also the most devasting form of energy when it comes to global heating.
The good news is that new technological advancements in solar energy, we can generate heat and steam at large volume as required by industry- cutting cost, reducing emissions and more importantly controlling the carbon footprint of industries.
Despite many attempts to ramp up renewable energy projects around the world, the consumption of coal is an all-time high in many countries. This must change at a global level. Worldwide industries constitute for about one-fourth of total carbon emission, With the transportation and domestic use of energy going down, industrial use is predicted to rise in the forthcoming decade.
As people around the world continue to migrate from village to urban cities and buying and consuming more goods, the industrial demand will keep on rising. This is the reason why the need to replace fossil fuel with solar heat is becoming more urgent.
Which brings us back to heat. Industries are the largest consumer of heat energy. Around 74% of the energy consumed by the industries is in the form of heat. Solar heat is still an unexplored but promising avenue due to reducing dependency on fossil fuels.
Integration of Solar Heat into Industrial Process
The most industrial process requires heating of both the fluid systems ( hot air steam, hot water) or a reservoir or both to run their industrial machines. The existing heating systems are based on the water getting converted into steam and the heat required is provided by non-renewables like petroleum, diesel, coal or electricity generated by different energy sources. Solar processes can contribute to reducing at least 20% of fossil fuel consumption. A limiting factor for solar heat integration is the scarcity of roof space to install solar energy panels.
The integration of solar heat into the industrial process can be done by the following three methods:
1) As a heat source for direct heating of circulating fluid
2) As an alternative source of heat for processes with low-temperature requirements
3) As an additional source of heat coupled with fossil fuel sources
With the first option, the storage will be an important component, since you need to provide heat throughout the day. With the second and third option, the solar heat will work together with fossil fuels when an additional source of heat is required.
Integration of solar heat with industrial process requires you to also create some remedial and control strategies to handle the non-continuous supply of solar heat. The accurate designing of solar panel systems can be carried out by accounting the energy demands and supply.
Performance and Cost of Integrating Solar Heat
Solar heat is been explored since the late 1970s and large scale solar energy projects have been deployed in numerous industries for demonstration purposes since the late 1980s. The most significant problems encountered are corrosion, leakage of pipes, faulty tracking system or dust collecting in the solar collectors. The advanced designs of solar collectors have addressed these issues but also made it more expensive. The capacity factor is also location specific and can range from 4% (e.g. Japan) to 16-20% (e.g. UAE/India) to 29% (e.g. Mexico).
Between 50-70% of the cost involved in implement solar heat is related to capital, the remaining 20-30% covers the installation and integration cost. In terms of individual components, the solar energy collector and installation accounts for 50%, piping and circulating system accounts for 20 %, buffer and storage systems accounts around 10%, control systems for 5% and rest 15% includes other miscellaneous expenses.
Most technologies and solar components are provided by local companies, similar to those provided in the residential Solar PV sector. However, for larger projects, there is an international transfer of technologies.
In the future, solar thermal components can be made more cost-effective when designed to deliver specific industrial process needs.
As a countries installation capacity tends to increase, the large installation will facilitate economic benefits and lower investment costs, thus increasing the projects overall economic viability.
Drivers and Barriers
The key benefits of adopting solar heat for the industrial process include
1) reducing the dependency of industries on fossil fuels
2) reducing the risk of associated with the rising price coal, petroleum and natural gas.
3) eliminating fuel cost
4) reducing carbon footprint
The current cost of solar collectors is controlled by relatively a small number of suppliers. Although these technologies are of high performance, the cost is not yet suitable for the global market. The previous experience of dealing with local authorities for solar components reduces the capital cost and improve business opportunities for local people.
The main barriers to increase the deployment of solar heat for the industrial process include
High initial investment and lack of financing options: All solar projects invites a high initial investment. Proper maintenance is required to operate the project optimally over its full life expectancy. It takes years before you first start making a profit from your installed capacity. The upfront costs are high and cannot be afforded by medium and small scale enterprise. However, large scale industries are already taking some small calculated step towards adopting this technology.
Fossil fuel pricing: In many countries, the fuel utilized by industries is subsidized to support industrial development. This makes fossil fuels cost-friendly when compared to solar heat.
Lack of research and design tools: There are very few institutes who are actively involved in researching solar heat technologies. As a result of which there is no complete information available regarding design guidelines and tools. Even for existing technology, the knowledge of optimum integration is scarce and as a result, the efficiency takes a toll. Training and dissemination of existing knowledge and concepts are needed to overcome this problem.
Public awareness: Probably the most significant barrier in deploying solar heat is the lack of public awareness. There are very few industries who have the first-hand experience of actually implementing the technology. Due to the high cost, many industries do not try for a trial and error method. This is likely a key barrier in large scale solar heat adoption. The economic and practical advantages of adopting solar heat are yet to be explored on a large scale.
Solar heat is an interesting arena to explore and could possibly become one of the greatest outcomes of solar energy advancements. Despite the technical potential, the actual implementation of solar heat is quite low. Policy makers need to invest their brain to achieve higher market penetration. To fight economic barriers, solar components can be dealt with local authorities, thus providing a mutually reinforcing strategy to support a healthy national industry.