Business Opportunities in Solar Thermal – Heating Applications

Within this section you will find

Solar Thermal Market Overview

Solar Thermal energy is the harvesting of heat from the sun to be used as heat energy
Using heat as heat can be very cost-effective, especially at lower temperatures, compared to using electricity from solar PV to generate heat
Solar water heaters are the most familiar example of solar thermal, though applications range from cooking to air-conditioning
Global installations are greater than 270 GW_th. Almost 80% is used for domestic water heating. Industrial process heat accounts for less than 1%

Low temperature – up to 70°C – Flat plate and Evacuated Tube Collectors
Medium temperature – 70-150°C – Enhanced Evacuated Tube, Compound Parabolic Concentrator
High temperature – above 150°C upto 250°C – Concentrating Solar Thermal

Typical application is water heating. Air drying is a niche application in this temperature range.
Flat Plate Collectors (FTC) can heat up to 60°C, and last longer than Evacuated Tube Collectors
Evacuated Tube Collectors (ETC) can heat up to 70°C, but the evacuated tubes are fragile and have shorter life. More than half the installed capacity in the world is of this type
Quality of water is a concern
- Systems without heat exchanger are cheaper, and can be used where water quality is good
- Heat exchanger is a must where water quality is poor, but cost is much higher
Solar water heating is a Rs.200 Crore market in India
Globally, China is the largest market followed by Europe, Japan, and India
- India’s target is 22 million sq.meters of collectors by 2022; China’s target is 300 M sq.mtr by 2020
Prominent companies in this sector include Emmvee Solar Systems (India), Genersys Solar (UK), Nuetech Solar System (India), Phoenix Solar (Germany)

The primary driver for this solar solution is the very large number of industrial applications that require process heat in this temperature range
- India alone is a 17 GW_th market in this temperature range
- Solar can potentially replace Rs.20,000 Crores that is currently being spent on fossil fuels
- Solar is more expensive than wood or coal, but very cost-effective against diesel or LPG
Enhanced Evacuated Tube – Variation of ETC that achieves higher temperatures by passing the liquid through multiple tubes. This is currently in early stages of commercialisation
Compound Parabolic Concentrator (CPC) – Comprised of rotated parabolic sections; can heat to higher temperatures than Evacuated Tubes. This technology is in late R&D stage

Prominent companies include Aspiration Energy (India), Edmund Optics (USA)

This is the domain of the concentrated solar thermal, where high temperatures are reached by concentrating the sunlight many times from the original.

Technologies in use include:

Parabolic Trough – Parabolic trough that concentrates light on a receiver filled with a working fluid. Temperatures range from 150-350°C
Linear Fresnel Reflectors – Long thin strips of mirrors focus sunlight onto an absorber. Features single-axis tracking. Temperatures can reach up to 750°C
Parabolic/Paraboloid Dish – Parabolic reflector (or mirrors in paraboloid form) with dual-axis tracking. Temperatures are in the range of 250-700°C

Incorporating into/with existing infrastructure and fuel
Weight reduction for mounting on prefabricated industrial sheds
Predominantly dairy and food applicants, many European installations as pilots/demos. Worldwide, only a few hundred installations currently exist.
Several Indian players are prominent players in this sector, including Taylormade Solar Solutions, Sharada Inventions, Megawatt Solutions, Clique Developments, and Thermax
International players include Industrial Solar (Germany), TrivelliEnergia (Italy), Solitem (Germany), and NEP Solar (Switzerland)