Approximately 50% of the world’s energy end-use revolves around heat, underscoring the importance of adopting innovative, sustainable, and economical heat solutions in tackling the climate change emergency.
With Russia’s invasion of Ukraine driving fossil fuel prices skyward, the European energy market is at the focal point of the transition since Europe’s reliance on natural gas is profound in both domestic and, commercial and industrial sectors. Remarkably, more than 40% of Europe’s industrial energy comes from fossil fuels. As nations grapple with these challenges, the quest for sustainable, reliable, and cost-effective energy solutions has never been more crucial.
Solar energy for electricity and heat has emerged as an immensely vital contender in addressing these pressing needs.
This article will explain the basics of solar thermal collectors, discuss how they can replace fossil fuels in industrial and commercial heat processes, and benefit from integration with thermal storage, heat pumps, and photovoltaic electricity.
Solar thermal collectors: The basics
Technological overview and history
Solar thermal collectors work by absorbing sunlight and converting it into heat. This heat is transferred, typically to water, air, or another fluid, that can be used immediately or stored for later use. The primary objective is to capture the sun’s energy and use it to produce heat for various applications, ranging from domestic water heating to industrial processes.
The use of solar heating dates back to ancient times. Ancient civilizations, such as the Greeks, Romans, Persians, and others, used passive solar designs to harness the sun’s heat in their buildings. However, the first modern thermal solar collector was constructed in the 18th century by the Swiss scientist Horace Bénédict de Saussure.
As our economy became increasingly dependent on fossil fuels, the technology saw little progress until the 1950s and 60s. It became popular during the energy crises of the 1970s, spurring research and development. Since then, solar thermal collectors’ efficiency, design, and application have evolved tremendously.
Major types of solar thermal collectors
There are a few types of solar thermal collectors, where the division is usually based on shape, technology features, target temperature, etc. Here are some of the most common ones:
- Flat Plate Collectors: These are among the most common solar thermal collectors. They consist of a flat plate that absorbs sunlight, converting it into heat. This heat is then transferred to the fluid passing through tubes attached to the plate.
- Transparent insulation-equipped Flat Plate Collectors: uniquely, TIGI developed a flat plate collector that uses transparent insulation on the sun-facing side to reduce energy losses. This allows for the robustness of the flat plate collector design with high efficiency even at high target temperatures or in cold climate conditions.
- Evacuated Tube Collectors (Direct flow and heat pipe): These consist of parallel transparent glass tubes containing an absorber tube. The space between the inner and outer tubes is evacuated, forming a vacuum, which is an excellent insulator.
- CSP (Concentrated solar power) collectors
- Parabolic Trough Collectors: Often used in industrial applications, these collectors have a curved, parabolic design. This allows them to focus sunlight onto a focal point, typically a tube containing a heat-transfer fluid.
- Linear Fresnel Reflectors: Similar in concept to the parabolic trough collectors but use flat or nearly flat reflector surfaces (Fresnel lens) to concentrate sunlight onto elevated tubes.
- Parabolic Dish Collectors: These are shaped like satellite dishes and focus sunlight onto a single point, usually a receiver placed at the dish’s focal point.
Solar thermal collectors: Advantages and disadvantages
Advantages
- Renewable and clean, with no carbon footprint: Solar thermal collectors harness the sun’s energy, a renewable, long-term, and sustainable heat source.
- Cost savings: No need for expensive, price-volatile fuels and low maintenance costs.
- Scalability and versatility: Solar thermal systems can be scaled to fit the need and integrated with existing heating systems for a single home or an industrial complex.
- Energy independence: Using solar thermal collectors reduces dependency on external energy sources, making users less vulnerable to energy price fluctuations and supply disruptions.
Disadvantages
- High initial costs and more extended payback period in low sunlight/ cold regions: The upfront cost of purchasing and installing solar thermal systems might deter potential users.
- Intermittence and weather dependency: solar thermal collectors depend on sunlight, i.e., cloudy or rainy days, which hinders their performance, necessitating alternative energy sources.
- Space requirements: These systems require a fair amount of space for installation.
- Heat loss: Though modern systems have improved immensely, there’s still some heat loss.
The opportunity for industrial and commercial systems
Solar thermal collectors are usually used in small residential systems for sanitary hot water because of the sweet spot between the cost and efficiency of solar thermal collectors for low temperatures.
Large-scale industrial and commercial uses requiring higher target temperatures and a more complex system solution are managed by advanced collectors, smart thermal storage, integration with heat pumps, and innovative control with cloud services. With the introduction of obligatory ESG reporting for large companies starting Q1-23, new regulations related to renewable heat, and the high prices of fossil fuels, this domain promises to be one of the most lucrative opportunities for renewable energy of the next decade.
Furthermore, using models such as “Heat-as-a-Service (HaaS), in which the user pays only for the heat consumed, can easily tackle any financial challenge, such as high initial purchasing and installation costs.
Combining cutting-edge technology with business excellence
IWhen integrated into a comprehensive and innovative system such as TIGI’s solution, solar thermal collectors promise unparalleled efficiency and reliability.
Combining innovative collector technology, heat pumps, thermal storage, and intelligent control systems with the HaaS model makes it evident that the future of heating is not just sustainable but also remarkably cost-effective.
Contact TIGI’s team today to learn about advanced, clean commercial and industrial heat production.
