ÎNSOL SOLAR ENGINEERING Solar thermal power plants

Since 1978 | ENGINEERING in Italy


INSOL® is a large European group generating hot water from the sun – since 1978 we have been producing solar thermal power plants for an equivalent area of about 30,000 m2. We manufacture solar thermal power plants producing domestic hot water, sanitary hot water and swimming pool heating. Our panels have a TITANIUM capturing surface (our patent), which allows for the heating of water even in winter or in low light conditions, unlike other systems. We manufacture plants ranging from 160 Lt, 300 Lt, 500 Lt, 1000 Lt, 2000 Lt up to 5000 Lt, including 1, 2 or more solar collectors. Our systems are suitable for: villas, swimming pools, hotels, sports facilities, industrial warehouses, commercial farms, restaurants, resorts, campings and any other place where the consumption of energy (both gas and electricity) to generate hot water is rather high.


  • Our production has been tested by the German scientific specialist press “Bild der Wissenschaft”. Thanks to its “Titanium” collectors, it has been defined one of the most dynamic companies on the European market for Research and Scientific Innovations in the sector and for their current applications on serial products, for energy efficiency and quality/price ratio.
  • Our solar thermal power plants provide the best performance thanks to a well-calibrated installation that we or our retailers carry out and that too often is neglected.
  • The best guarantee we can offer to our customers is our 40 years of activity, know-how and experience.



We make a high-end product since our panels have a TITANIUM capturing surface, which allows for the heating of water in winter or in low light conditions, unlike other systems.

Example of a most common Solar Thermal Power System: 160lt and 300lt hot water production

  • Brand : INSOL Made in E.U. Solar thermal power since 1978.
  • Models : ST 160 or 300 Gold Titan (The data for the ST 300 are shown in red.)


The solar thermal power system consists of n. 1 (2) solar collector(s), with a total gross area of 2.10 sqm (4.20) and from a 160 Lt (300) tank. For the best performance, the system should be pointing South. In any case, the proximity to the East or West also allows a good performance. A supporting frame (hot-dip galvanized to avoid any type of corrosion and rust) will be provided for fixing the system to the roof and, if desired, for giving the roof a different inclination. In case of installation on a terrace, a different frame must be used (with a small additional cost in comparison to the above-mentioned frame).


Attention: Our panels are of the “FLAT” type and not of the “VACUUM TUBE” type. We have stopped producing vacuum tube panels because they are not suitable for hot latitudes but more suitable for cold temperatures (e.g. Northern Europe, Canada, etc.). In Italy, the tubes, being made of glass and suffering from our strong solar radiation, after a few years tend to crack and the vacuum is lost, becoming no longer functional.

The collectors have the following characteristics:

  • Panel with perimetric metal parts and frame in anodized aluminium with high anodization thickness for high protection against atmospheric agents. Also suitable for seaside houses (affected by saltiness). •Capturing plate made of copper tubes and copper plate, treated with TITANIUM, for a performance higher by 30% compared to traditional collectors.
  • Ultrasonic welding to optimize heat transfer between the tubes and the capturing plate.
  • Back insulation made of mineral wool.

•Multiprismatic, tempered, anti-hail and non-reflective crystal cover to improve the diffraction of sunlight and improve the greenhouse effect inside the collector obtaining the highest heat output.

This crystal complies with the New Safety Regulations and is designed as non-reflective, to avoid annoying reflections banned by municipalities. N.B. These collectors have the necessary certification to apply for State Incentives.


  • Supporting frame made of hot-dip galvanized steel, to contain the collector(s) and to provide them with the necessary inclination, if necessary.


  • N.1 160 (300) lt solar tank/ boiler with double internal enameling of 80/120 microns, with flanged copper tubes exchanger, complete with the anode and perfect thermal insulation in polyurethane foam up to 55 mm of thickness. In the boiler, the water stored in the absence of sun (for example in winter) is kept warm for 3-4 days.


The distribution of sanitary hot water, coming from the solar system, can happen in four ways:

  • “CONNECTION 1”. DIRECT (included in the installation price)

It connects the water coming out of the tank-boiler to the nearest hot water connection in the apartment (sink, shower, etc. …) and uses the boiler as a huge high-temperature water heater. It manually switches, with ball valves, in case all the hot water produced by the panel has been used. •“CONNECTION 2”. WITH MANUAL SWITCHING

In the event of consumption of the entire hot water tank, you can manually switch the system, by using the ball valves located under the boiler. These will send the water to the boiler (at the entrance of the sanitary water), which will switch on and heat the water, then send it to the apartment. •“CONNECTION 3”. FOR AUTOMATIC SWITCHING WITH SOLAR CONTROL UNIT

With this solution, the system can be connected to the input of the boiler itself, connecting the water coming out of the tank-boiler to a solar control unit on the line of the system of production of sanitary hot water, thus automating any integration.


If the boiler is to be installed elsewhere, not under the solar collector, then the following items must be installed as it is no longer a natural circulation system: -Heat resistance probes for temperature (Delta) control

-Circulator for the continuous transport of high-temperature glycol from the panels to the boiler

-Electronic solar differential control unit for the control of resistance thermometers, which can activate the pump.

-Electrical connection system from the probes to the control unit -2 expansion tanks of the primary and secondary circuit of 24 lt. -Miscellaneous accessories for hydraulic connections

-3-way solenoid valve motorized for switching to the boiler.

These elements also automate the automatic integration of the boiler and do not require the installation of the control unit under the boiler (“CONNECTION 3”). Installing these elements also automates the automatic integration of the boiler and therefore the extra cost of “CONNECTION 3” is no longer required. N.B. Keep in mind that in connections 2-3-4, the boiler will provide the integration with the water heating, not by taking the water at the temperature of the aqueduct (especially in winter when it is at very low temperature), but by the solar circuit whose water, even if at non-optimal temperature, will always be between 25 and 35° and therefore the boiler will only have to raise the temperature up to the required one. Therefore, even if all the hot water has been consumed, gas consumption will be very low.


Our special technological innovation allows our collectors to capture infrared radiation, even in the

event of not too heavy cloud cover. This is due to our patents, the excellent design and the high-quality of the system.


Our panels are glazed and the internal capturing surface has a TITANIUM treatment, capable of

capturing a range of higher solar frequencies, including those that filter even in the presence of

light cloud cover. They have a performance higher by 30% than “paint” collectors, i.e. black painted

collectors, and 40% higher than traditional solar panels. This feature is also reported in some tests

compared to other European productions of the German magazine specialized in the sector, of which

we enclose the final report, where our collectors proved to be those with the highest thermal output

compared to the other collectors tested.

Easy system operation

The water coming from the water network inside the tank (which works like a large and highly insulated water heater) heats up in the coils where the glycol liquid of the sealed solar circuit circulates at a very high temperature. The heat exchange between the coils and the water inside the tank has a high efficiency since in summer the glycol can reach temperatures close to 120/130°C and in winter even 50/60°C. The hot water obtained will serve the home user, using the existing pressure of the aqueduct or autoclave. So the pressure on the taps at home will remain the same.


The total weight of the system on the roof is kg. 140 (230) when empty and kg. 290 (520) when full. Our plants are exported to 48 countries and some of the certifications obtained in those countries are listed in the attachment, which we invite to review.