The benefits of solar thermal
Installing solar thermal hot water heating requires minimal upheaval and can deliver considerable cost savings, making this type of renewable technology a practical and cost-effective option for new-builds and existing properties.
- Produces up to 60% of a property’s annual hot water – as much as 100% in summer.
- Suitable for every home, whether new build or retrofit.
- Low-cost investment.
- On-roof and in-roof solar panels available.
How does solar thermal energy work?
Energy from the sun warms fluid in the solar panels. When the fluid reaches a useful temperature, it is pumped to a coil in the bottom of a solar cylinder. The solar coil heats the cylinder water for domestic use.
If the cylinder’s thermostat detects that the solar panel has not collected enough energy to heat the water to its pre-set temperature, it allows the main heat source to top it up (i.e. a boiler).
The control panel can be set to optimise efficient use of the solar panel and ensure hot water is available at the times you need it.
The Components of a Solar Thermal System
Solar Collectors: The heart of a solar thermal system, solar collectors are responsible for absorbing sunlight and converting it into heat energy. These panels are typically made of special materials designed to efficiently capture and retain solar radiation.
Heat Transfer Fluid: A heat transfer fluid, such as water or a specialized thermal fluid, circulates through the solar collectors, absorbing the heat they capture. This heated fluid is then transferred to the storage and distribution system.
Storage and Distribution System: The heated fluid from the solar collectors is stored in a well-insulated storage tank or sent directly to the target application, like heating water for domestic use or space heating. In some cases, the heat can also be converted into electricity using a steam turbine in a solar thermal power plant.
How Solar Thermal Panels Work: The Process
Absorption of Solar Radiation: Solar collectors are strategically positioned to maximize sun exposure. When sunlight strikes the surface of these panels, they contain a dark-colored absorbing material that converts sunlight into heat. This process is highly efficient, even in cloudy conditions, making solar thermal panels a reliable energy source.
Heat Transfer: As the solar collectors absorb solar radiation, they transfer the captured heat to the heat transfer fluid passing through their tubes or channels. The fluid’s temperature rises as it circulates through the collector, carrying the captured energy.
Storage and Distribution: The heated fluid is then directed to a well-insulated storage tank, where it can be stored for future use. In residential applications, this stored heat is often used to heat water for domestic purposes or for space heating. In larger installations or solar thermal power plants, the heat may be used to generate steam, which drives a turbine to produce electricity.
Backup Systems (Optional): To ensure a continuous supply of hot water or heat, especially during periods of low solar radiation, some solar thermal systems have backup heating sources. These backup systems, like electric or gas heaters, can provide additional heat when solar energy alone is insufficient.
Solar Thermal FAQs
The sun is amazingly powerful! The tiny fraction of the sun’s energy that actively reaches earth is enough to meet our energy needs many times over. In fact, every minute, enough energy arrives at earth to meet our energy demands for a whole year – if only we could harness it properly.
Our customers are always surprised at how much water our solar installations provide. Reliable studies have shown that systems installed in the UK can provide an average of about 70% of the hot water requirements over the year. Systems work surprisingly well in the winter (16-18% of hot water needs being met in December and January) and almost 100% of hot water needs being met in July and August.
Even when sunlight is diffused through cloud, you’d be surprised at the amount of heat that the solar panels can still collect. And nothing is wasted – all the heat collected is used to pre-heat the cold water entering from the mains. So even in winter you won’t be heating your water from scratch; your panels will work hard all year round to save you money.
Firstly, a solar collector (more commonly known as a solar panel) on the roof of your home traps the heat from the sun. The panel is filled with a non-toxic, special liquid that circulates within the panel and transfers heat to the hot water cylinder within your home. The temperature of the liquid is constantly monitored by an electronic controller. Whenever the collectors are hotter than the cylinder, the circulating pump is switched on to transfer the heat to the cylinder.
Panels work best when facing due South, yet they also work at a suitable yet reduced capacity facing due East or West as facing up to 90º from south will typically result in only a 20% drop in performance! Panels don’t need to be roof mounted either, we build frames to allow them to be ground, wall or roof mounted.
No planning permission is needed in the vast majority of cases. If you live in a conservation area or in a listed building planning permission may need to be obtained.
No regular system maintenance is required at all. The solar panels have a self cleaning coating, which means the rain will keep your panels clean for you.
Ready to embark on your renewable energy journey?
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