Solar thermal and solar PV both utilize sunlight although, the mechanisms of the two systems are incredibly different and produce different outcomes. So what are the differences?
Solar thermal panels utilize the sun’s energy to heat water. Think ‘solar energy to thermal energy’.
In thermal systems you can choose between two ‘panel’ types: evacuated tubes (as seen in the above image) or flat plate systems (which are often the cheaper option).
In both instances, the panels are connected to your homes heating and water systems and are typically used in accordance with your boiler and/or immersion heater to provide free hot water.
So how do they work?
Inside thermal panels is a ‘transfer fluid’ (a mixture of glycol and water – which prevents freezing during winter), this fluid is heated by the sun and passed through a ‘heat exchanger’ which further heats the water inside the cylinders. Then voila, you have renewable home heating.
Benefits and Limitations of Solar Thermal Panels
Thermal panels are more space efficient than PV and your home requires less panels fitted to the roof to get the required results. Moreover, the technology is less complex than PV and it is a great renewable method for heating water.
However in winter months, thermal is a less efficient method – unless you purchase ‘thermodynamic panels’. Moreover, not all boilers are compatible with thermal and so there may be additional costs involved with buying a new water tanks and as the final point and most important point, the versatility of thermal is incredibly small – you are limited to only heating water.
Solar PV panels utilize sunlight to generate electricity. The panels require an inverter which converts the current from AC to DC which allows you to use it on your electrical appliances at home.
How do they work?
PV panels are more technical than thermal panels. Simplistically, PV panels contain silicon cells which ‘react’ to sunlight which enables creates an electric which is transformed to usable electricity for your home.
Benefits and Limitations of Solar PV Panels
The greatest benefit of having PV over thermal panels is that PV is incredibly versatile. It can power your homes’ appliances, electric vehicles and even your water and heating system (if it is an electric based system). Moreover, if you create ‘too much’ electricity, you can send the excess to the grid and generate money from your microgeneration system and, with a solar battery storage system, you can ‘save your electricity for later use’. It is for these reasons that we love solar PV systems.
As for limitations, you will require a few more panels on your roof to attain a desirable amount of electricity. Although, even with one or two panels you can generate enough electricity to power some of your electronic appliances. It really depends on how much you want to generate.
It is true to say that both systems have their advantages and both have disadvantages which do often overlap. Both require roof space and incur upfront costs. However, both save money in the long run and generate renewable energy which is essential as we move towards a net-zero emission future.
Whilst this may come with some bias, as we are solar PV installers, the versatility that PV offers make us conclude that PV systems are the better option. Purely since clients can use the electricity anyhow they like and can heat water with the panels. Therefore, you can do more with your purchase.
Huub is a Dorset based, British company that constructs modular, timber framed, solar powered garden buildings. Huubs are built in an off-site facility in Dorset and offer a great opportunity to generate solar energy and add additional space to your home at a relatively low cost (approximately £1500 per m2).
For more information about Huub visit our website: https://www.huub.house/
Email us at: firstname.lastname@example.org
Or phone us on:01305 250429
Photo Credit: energysage