TRIAN-S is a prototype of a wide purpose offgrid solar electricity production unit with usable room under the solar panels. The general idea is to take in use of the space under ground mounted solar panels, so we can economize resources of land.
Frame (stand) of solar panels makes the room we can use for multipurpose: from storage to accommodation. Roof is made from solar panels, which are producing energy. Energy generation capacity is depending on type and number of panels. It could be 2,5-5 kW and yearly production 2500-5000 kWh.
Complexity and cost of building and operating
Building and operating:
Medium (partially DIY, medium maintenance/operating complexity)
High (>500 EUR)
Operating costs are low (full DIY, low maintenance and operating complexity, low cost <100 EUR), but the building materials cost is over 500 EUR (approx min 5000 EUR, depending also on materials cost, availability, transportation and prefabrication).
Description of the solution
Trian-s is a relatively low-cost multipurpose offgrid energy production unit with usable room, which can also be placed in a naturally sensitive environment. Its triangular shape allows, in addition to the cheap construction cost, to place the solar panels at the right angle. At the same time, solar panels form the roof of the building. The resulting building (ca 15 m2) can be used for many purposes: warehouse, tool shed, cooling storage, accommodation, sauna, etc. The building consists of 3 walls, a floor and solar panels roof. Building is placed on 9 stone blocks and needs no specific foundation.
It is also possible to combine building units in different ways, resulting in a larger building and more options for use.
The use of the building reduces the ecological footprint due to environmentally friendly electricity generation and the integration of the materials used.
Technical description for one unit
- Dimensions (L x W x H): 4x4x4m
- Number of walls: 3
- Bottom area: 16 m2
- Useful space area: 14 m2
- Electricity generation capacity: 2,5-5 kW
- Annual electricity productivity 2500-5000 kW (as of Estonia)
- Total battery capacity: 400 Ah (24 V)
- Output voltage 24 V (DC), 230 V (AC-main output)
- Number of expansion modules: not limited
- Life expectancy (80% of resources are reusable, except batteries): 25 years
Skills, tools & materials required
The complexity of the building is medium and requires basic skills of general building and carpentry . Special skills for electric installation is required and might be demanding specific certification, depending on location.
For installation of the electrical system and its components, it is mandatory to have basic understanding of electricity, voltage, current and resistance, and in some areas even connecting PV-panels will require the work of a licensed electrician. In order to calculate needed power and load one should know Ohms law. The basic theory is easy to learn from internet, and useful links to this are the following:
“Voltage, Current, Resistance, and Ohm's Law”
A basic setup of hand tools are required for the build and most of the parts can be prefabricated and processed before arriving to the build site. Construction does not generate waste at the construction site, as the building consists mainly of wood and its parts are intended to be prefabricated at the factory. It can also be built on site, according to the drawings available. Only hand tools are needed for construction.
- 9 stone blocks
- wooden beams 50x150x5000 mm, 12 pcs
- wooden boards 22x10x4000 mm, 8 pcs
- lining boards for external walls, 30 m2
- screws, edge stains
- OSB construction plate 22mm, 16 m2 (upper layer of the floor; double if also lower layer is required to carry the optional insulation)
- zinc sheet for the roof
- windows according to the needs and a door
- solar panels 250-400 W, 8-12 pcs.
- offgrid inverter 5 kW
- batteries 200 Ah, 4 pcs.
- wires, fuses
Find out what you are allowed to do in your local area according to current regulation.
Conclusions and errors to avoid
In order for a building to be durable and efficient, construction must be carried out in accordance with the drawings.
Cost & Life cycle analysis
Trian-S is designed to last at least 25 years, when it does not require maintenance, except for routine building inspections and minor repairs.
25 years of electricity generation (at current prices of 40 EUR per MWh) would be up to 5000 euros, which could be saved (in addition to the grid costs) by using locally the electricity of the Trian-S unit.
Because the energy is produced and at the same time maintenance costs are close to zero, Trian-S saves resources and recovers construction costs, excluding the costs normally associated with electricity, which in some places can amount to tens of thousands euros.
Since the structure of the building is mostly consisting of wood, it locks in carbon for the duration of its lifetime. The total footprint of the building depends on the choice of insulation and other parts. Construction does not generate waste at the construction site, as the building consists mainly of wood and its parts are intended to be prefabricated.
For LCA connected to the PV-system, please follow the following link to get to the PV introduction:
Step by step guidelines for building the solution
5: placing and fixing the triangles on the floor beams at equal intervals, so that the distance between the outer triangles is 4 m
6: installing 8 planks (into the pre-prepared mortises in the middle triangle beams) crossing the top of the triangles for the roof support
7: installation of sheet metal on the roof
No videos available
Soonlepa, Hiiumaa island, Estonia
Accessible only for registered persons during organized workshops.
Who are the people, community, institution and/or organisation operating the prototype?
NGO Soonlepa Arenduskeskus
Tõnis Kasemägi - inventor and engineer
Author of the content
Tõnis Kasemägi , Soonlepa Arenduskeskus NGO, tel.+372 5017115