In a world where energy demand continues to constantly increase and concerns about climate change are more pressing than ever, the search for sustainable and economically viable energy sources becomes essential.
In this context, solar thermal energy stands out as a promising solution for energy and economic savings, compared to other energy sources.
In this article, we explore how solar thermal energy compares to conventional energy sources and its counterpart, solar photovoltaics, to demonstrate its effectiveness in saving energy and costs.
Solar thermal energy vs. conventional energy
To understand the magnitude of the energy and economic savings that solar thermal energy offers compared to conventional energy sources, it is necessary to examine some concrete examples.
Residential water heating
A common example is residential water heating. In many homes, water heating is carried out by gas or electric boilers.
These methods are effective, but also expensive and inefficient in terms of energy. Solar thermal systems, on the other hand, capture the sun's energy to heat water, significantly reducing energy costs over time.
In addition, solar thermal collectors have a long useful life, which means continuous economic savings.
Space heating
Solar thermal systems can be integrated into existing infrastructure to provide efficient heating and reduce operating costs by 20% or more.
Industrial processes
In industry, solar thermal energy is used for process applications such as steam generation and fluid heating. Companies around the world are adopting this technology to reduce operating costs and comply with stricter environmental regulations.
An example is the brewing industry, where production plants have implemented solar thermal systems to heat the water needed in the brewing process, saving considerably on energy costs.
Profitability of a solar thermal installation
The profitability of a solar thermal energy system is usually calculated over several years, often considering a return on investment (ROI) period that is usually between 5 and 10 years. This time period can vary significantly depending on geographic location, system size, initial costs, amount of power required, and available incentives.
In general, as initial costs are reduced due to declining component prices and potential tax incentives, the time required to recover the investment shortens.
As the system continues to operate after this recovery period, energy cost savings translate into net profits. The durability of system components and efficiency over time also influence long-term profitability.
Comparison with photovoltaics
The main difference lies in the way they convert solar energy into usable energy:
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Solar thermal energy: Converts solar radiation into heat for applications such as water heating, space heating and industrial processes. The efficiency of solar thermal systems for these applications is high, since no energy is lost in the conversion of heat to electricity.
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Photovoltaic solar energy: Converts solar radiation into electricity through photovoltaic panels. Although it is a popular technology for electricity generation, there is a loss in the conversion of heat to electricity, making it less efficient for direct heating applications.
Energy saving
In terms of energy savings, solar thermal is usually more efficient than solar photovoltaic in water and space heating applications, as there is no loss in conversion. Additionally, solar thermal systems are typically more affordable in terms of upfront and maintenance costs compared to photovoltaic systems.
Economic savings
In terms of economic savings, solar thermal energy also offers notable advantages.
Solar thermal systems have a faster return on investment in water heating and space heating applications, meaning homeowners and businesses can recoup their investments more quickly through reduced energy bills.
Additionally, solar thermal systems typically have longer lifespans and lower maintenance costs than photovoltaic systems, further improving their economics.
Real world examples
A notable example of energy and economic savings through solar thermal energy is found in the Solar Energy Research Park in Spain.
This park uses solar thermal systems to generate heat at high temperatures that is used to produce electricity. Through this technology, significant savings in operating costs have been achieved compared to conventional energy sources.
Another example is the solar heating system at the Pitié-Salpêtrière Hospital in Paris, France.
This hospital uses a highly efficient solar thermal system to provide heating to its facilities. The result has been a notable decrease in heating costs, allowing the hospital to reinvest these savings into improving healthcare.
Conclusion
Solar thermal energy stands out as a valuable option for energy and economic savings compared to conventional energy sources.
Its applications in water heating, space heating and industrial processes offer significant advantages in terms of efficiency and costs. Furthermore, compared to solar photovoltaics, solar thermal often proves to be more efficient and economical in direct heating applications.