Evacuated solar tubes and installations

"Evacuated refers to vacuum-sealed. Learn about evacuated solar tubes, a heat-generating technology developed for northern European regions. Evacuated tubes work due to the sun's short-wave radiation converting to long-wave radiation. Installing this solar energy system will enhance your heating capabilities and bring it up to modern standards."

Stuart Lovatt
Creator of Power My Home.

"The solar tubes you recommended are very efficient as we only have to top up our system with the gas heater for about an hour a day, even though the weather has been very wet."
Mr. Greenough, Denbigh.

The best solar tube technology includes a patented Low E glass. These use a unique 'low-iron' glass formula that has reduced reflective properties and increased absorption. The glass surface has a 360-degree absorption ability with better annual performance than flat-plate technologies. The reason is heat retention and production at lower outdoor temperatures. Each tube is just like a thermos flask. Once the heat is in, it becomes trapped.

The science bit.

A popular solar technology before the advent of PV solar systems:

• A solar tube system heats up due to the sun's short-wave radiation output converting to long-wave radiation. This process creates heat.
• The variable speed controller circulates based on temperatures within the panel.
• The pump circulates a Glycol solution through the hot collector and backs down through a heat exchanger.
• The system automatically shuts down if the collector temperature falls below the cylinder temperature.

The UK receives 60% of the sun's radiation compared with the equator. Each square metre receives 900 to 1,300 kWh annually. All can be captured and diverted into your hot water tank with evacuated tubes. Evacuated tubes use a thermos flask principle that allows each vacuum tube to get hot regardless of external air temperature:

• The direct-flow system benefits from higher performance with fewer vacuum tubes.
• Heat pipes channel heat to the header unit and can disassemble more easily for self-building.

Common questions about evacuated tubes

What about Combi boilers?

Combi boilers aren't possible in most cases. We would need to re-install a hot water tank. Most homes with Combi's won't have the space to install a hot water tank.

Can I install evacuated tubes myself?

Yes, it is possible to self-install with a local tradesperson.

Is there a danger that it could get too hot?

The system may never rise above 85° Celcius.

Why update my hot water tank?

Older 'copper' hot water tanks run exceptionally inefficiently, especially after many years of use. Limescale will reduce performance even further. When installing evacuated tubes, it's essential to establish an efficient tank to get the most out of your system.

Will it contribute to my central heating?

We would need to check if your management system is suitable. In most cases, evacuated tubes can contribute to your central heating via underfloor heating. Evacuated tubes are the most efficient solar heating technology, but PV-heating converters could be an option.

How long will it take to install?

Installations complete in one to two days.

Do I require planning permission?

Listed buildings, conservation area homes, and national parks may require permission. Please consult with your local planning officer.

Do evacuated tubes work on cloudy days?

This question depends on the density of the cloud. In average cloud density, solar panels use passive energy. With dense cloud cover, probably not.

Can you upgrade my hot water tank?

In most cases, we recommend updating the hot water tank to allow a secondary connection and improved insulation for an evacuated tube installation.

How long do evacuated tubes last?

A system will easily last twenty-five years.

Specifications:

2 SQM
Length: 1642mm x Width: 1392mm x Height: 102mm.
Aperture Area: 2.0 m2.
Efficiency: 95%.
Max Power 1236 W.

3 SQM
Length: 1642mm x Width: 2082mm x Height: 102mm.
Aperture Area: 3.0 m2.
Efficiency: 95%.
Max Power: 1858 W.

The history of solar heating.

This technology was invented in 1896 by simply painting boxes black with glass bottles filled with water that trapped solar energy to heat the water inside. William Bailey created the first thermosyphon system that led to successful commercialisation. Solar thermal technology has come a long way, improving its efficiency using insulation technology.

New world savvy.

"I've witnessed many fantastic changes, innovations, and installation companies come and go. My fellowship with ethically-minded MCS solar panel installers goes back decades. Today, I offer my experience to ensure you gain real independence from this crazy geopolitical world."

Stuart Lovatt
Power My Home Solar Panels
Sundial House, Panton Road, Chester CH2 3HX.
01244 722 607