FAQ: Frequently asked questions ☀ Autarq: Next Level Roofs
Planning & Installation
As a rule of thumb, 12 solar roof tiles are installed per square metre.
Much like traditional photovoltaics, a roof orientation to the east, south and west is best suited for an Autarq solar roof. Roofs facing east and west should not exceed a roof pitch of 45° in order to get as many hours of sunlight as possible. Since solar roofs are nowadays installed primarily to generate electricity for self-consumption – and not to feed power into the public grid – using an east or west-facing roof has a decisive advantage: the distribution of power generation throughout the day is much more even than with a south-facing roof. Although the latter achieves a high yield peak at midday, most residents have little need for electricity at this time of day. With a particularly low roof pitch, even a north-facing roof can be covered with Autarq solar roof tiles.
This question can be answered by an electrician on site. A meter box that is 50 years old or older will most likely need to be replaced because it no longer complies with the latest regulations. Until now, older fuse boxes have been tolerated – but the integration of a solar roof solution requires an intervention. Due to this intervention, an older distribution box may lose its toleration status and must be upgraded to comply with current regulations.
No – and that is what makes the Autarq system special. As soon as the Autarq wire harness has been installed by qualified experts, a roofer or carpenter can tile the roof with Autarq solar roof tiles. The transfer point for the electrician is the Autarq PV converter in the attic: All cables from the roof are routed there. Connecting the standard PV inverter and, if applicable, battery storage and starting up the Autarq system may take place at a later time. The roofer and electrician don't have to be on site at the same time.
Basically, any roof with a pitch angle between 20 and 60 degrees is suitable for Autarq solar roof tiles. A lower or higher roof pitch is also possible – but before that we should talk.
Yes. In this respect, there are no differences between conventional roof tiles and solar roof tiles. The recommendations and installation instructions provided by the manufacturer of the carrier tiles as well as the rules and regulations of the Central Association of the German Roofing Trade apply.
The cables laid horizontally (on the underside of the roof battens) are called bus cables. They serve to connect the solar roof tiles to each other. Junction boxes are attached to the bus cables at a distance of two tiles: This is where two tiles are plugged into the wire harness. A bus cable may be a maximum of 10 m long. For most roofs, this is perfectly sufficient; for wider roofs, several solar roof tile fields are arranged next to each other. Don't worry: The field planning is always done by Autarq and made available to the executing roofing company. At most, small adjustments have to be made on site. The vertical cables (along the counter battens) are called branch connectors. They are used to connect the bus cables to each other. Care must be taken to run the positive and negative cables separately: Positive cables (red) run along a counter batten. Negative cables (black) run along the next counter batten, i.e. at a distance of approx. 70 cm.
The cable run between the Autarq solar roof and the Autarq PV converter should be kept as short as possible to minimise line losses. It is not without reason that the Autarq PV converter is installed close to the roof. The cable losses between the Autarq PV converter and the standard PV inverter are significantly lower – therefore longer distances can be bridged, for example to a technical room in the basement.
The vertical branch connector cables are attached along the counter battens using standard nail clamps.
On the back of each Autarq solar roof tile, there is a connection cable with a two-pole connector. This connection cable is plugged into a junction box on the horizontal bus cable. It 's very easy to see whether the connector and junction box have been plugged together correctly: The plug has a clearly visible "bump" that must point upwards when plugged in. In addition, + and - are clearly marked on the plug and junction box. Two Autarq solar roof tiles must be plugged into each junctio box. If only one solar roof tile is plugged in, it won't work.
The connection between the horizontal bus cable and the vertical branch connector is not a plug-in connection, but a penetration crimp connection. This is currently made on the roof by an Autarq wire harness expert using a special tool (crimping pliers). Good to know: We are currently working on the next cable generation to enable a tool-free connection of the cables – and to make the installation of an Auarq wire harness very easy for all interested roofers from 2023 onwards. The Autarq Academy will offer professional training in due course.
No. it doesn't make sense to lay bus cables and branch connector cables in advance: If the solar roof is to be extended, the roof area in question must be opened anyway – that's when the wire harness can be extended in the appropriate place. The cable running from the house to the roof is something else: It may well make sense to lay a solar cable with a 10 qmm cable cross-section as an "empty cable". This could be more difficult at a later stage because the attic conversion may already have been completed.
Conventional solar modules are connected in series. There, all modules of a string should always be irradiated with the same intensity: Even small shadows have a large effect on the entire system, because the modules with weaker irradiation "slow down" the modules with stronger irradiation. In contrast, Autarq solar roof tiles are connected in parallel. This way, each pair of roof tiles makes its contribution without influencing other pairs: A strongly irradiated pair delivers more power, a weakly irradiated pair delivers less power – and everything is "collected" on the bus cable.
Roofing companies can buy Autarq solar roof tiles from building materials dealers. Roofers or carpenters install the Autarq system – during the first few installations they get support from the Autarq Academy team.
To all the roofers and carpenters out there: Don't worry, with the support of the Autarq Academy, you'll be a pro in no time. We offer digital tools and application training in certified courses – and we will assist you in the installation of your first Autarq solar roofs.
Due to the intelligent, three-step installation of an Autarq system, the duration of the actual tiling is optimised. Typically, the Autarq wire harness is attached to the battens within four to eight hours. After that, the Autarq solar roof tiles can be installed. This takes only 10 to 15 seconds longer per tile than installing a standard tile. An electrician then connects the system to the Autarq PV converter in the house and starts it up. Done! Good to know: During installation, power continues to be drawn from the public grid.
The degree of self-sufficiency, i.e. the proportion of electricity consumption that can be covered by self-generated electricity, is a good indication for a commercially reasonable solar system dimensioning. Currently, a value between 65 % and 75 % is considered particularly economical.
Yes, the standard PV inverter of an Autarq system is prepared for operation with battery storage.
Yes, but there is a cable with a connector on the back of each Autarq solar roof tile. Hence, the solar roof tile is laid on the roof batten as usual, and in the second step the cable is plugged into the Autarq wire harness. Storm clips or screw connections can be attached as usual. Depending on the roof tile model, the sliding range may be somewhat limited compared to conventional roof tiles. This is because the Autarq solar roof tile in the upper row must not rest on the glass surface (solar module) of the roof tile in the row below. For this reason, it is imperative that the exact batten spacing is maintained when battening. At very low temperatures (around freezing point), the connectors are somewhat less elastic: More force is required when inserting the plug, but there is no danger or brittleness.
The first Autarq solar roof projects that a roofing company carries out with us as part of the Autarq Partner Programme are accompanied on site by a member of the Autarq Academy. If questions arise during subsequent projects, our Autarq experts are available to the roofers by telephone via our hotline.
Yes, depending on the standard PV inverter used, this is possible.
The recommended pattern for Autarq solar roof tiles is off-centre, just like conventional roof tiles. The recommendations and installation instructions provided by the manufacturer of the carrier tiles as well as the rules and regulations of the Central Association of the German Roofing Trade apply. When covering particularly flat roofs, additional measures may be necessary on the sub-roof (standard roof pitch: at least 30° for roofing in rows / at least 25° for bonded roofing).
The transport cable into the house (solar cable with 10 qmm cable cross-section) must be laid at right angles: According to the professional rules of the electrical trade, cables must not be pulled diagonally across the roof, but either vertically (along the counter battens) or horizontally (along the roof battens).
Each solar roof tile field can hold up to 200 Autarq solar roof tiles – but also significantly less than that. The number depends on the conditions on the roof. The number of fields per roof surface is unlimited. Each solar roof tile field is constructed in the same way: with horizontal bus cables and a vertical branch connector cable, which is extended into the house with a transport cable (solar cable with 10 qmm cable cross-section).
The size of the battery storage depends on the power consumption and the size of the solar roof. Normally, for smaller solar solutions (less than 10 kWp), it is recommended to choose a battery storage approximately the same size in kWh as the solar system is in kWp.
Before tiling, the Autarq wire harness is installed along the underside of the roof battens. This is done by an Autarq wire harness expert or a specially trained Autarq-certified roofer. Once the Autarq wire harness has been installed, nothing can go wrong with the electronics: When tiling, the cable on the back of each solar roof tile merely needs to be plugged into the cable harness. For the first few installations, Autarq lends the roofer a measuring device, which counts the solar roof tiles during the tiling process. After each tile has been successfully plugged in, a sound signal is emitted to confirm this. Once a solar roof tile field has been completely covered, the number of connected tiles can be read off the measuring device. This number – and the corresponding value – must be noted down in the roofing record. Roofing companies can purchase the measuring device from Autarq for future projects after further solar roof projects have been realised.
No. The horizontal bus cables are fixed along the underside of the roof battens. The vertical branch connector cables are used to connect the horizontal bus cables. They run along the counter battens.
Depending on the roof tile model, the sliding range may be somewhat limited compared to conventional roof tiles. The reason: An Autarq solar roof tile in the upper row must not rest on the glass surface (solar module) of the roof tile in the row below. Therefore, the exact batten spacing specified by Autarq must be observed when battening.