Grid connection concept for PV plants: planning the grid connection
Grid connection concept for PV plants creates an efficient grid connection, which is decisive for the success of your photovoltaic plant.
We support you from the first grid idea to the final coordination with the grid operator, technically sound and rule-compliant. This includes the grid enquiry, which we coordinate expertly with the grid operator. The grid concept defines how the PV plant is connected to the grid, what capacity the connection can take and what requirements the grid operator sets.
In Austria, the grid connection process with grid connection application, connection assessment and connection concept is described in the TOR for generators and follows the procedure in the grid operator's general terms and conditions. The application contains, among other things, a site plan, the desired start of feed-in, maximum capacity in kW, plant type and expected annual energy volume. The grid operator assesses the connection, including grid perturbations, and prepares a connection concept, the period of validity of which depends on the rules in force and the grid operator's conditions. If the requested capacity is not possible at the connection point, it proposes alternatives, such as a capacity limit or a different connection point. Grid access agreement and capacity reservation follow, and their duration and lapse depend on the rules in force and the connection conditions. For the cost estimate for the grid connection, the deadlines set in the grid terms and conditions apply. The grid operator sets the commissioning date in the contract; deadlines for this and possible exceptions, for example for official procedures, follow from the rules in force and the grid access agreement. For a complete application, the grid operator can require land zoning.
Which requirements apply depends on size: under the TOR for generators, plants below 250 kW are type A, larger ones types B to D with additional conformity evidence; the TOR version in force is decisive. At medium-voltage level, depending on plant type and TOR version, requirements for fault ride-through and dynamic reactive current support apply; for reactive power, the grid operator specifies the method. The design is SF6-free and is secured with calculations for load flow, short circuit, loss optimisation and thermal dimensioning. We assess grid compatibility on the basis of grid perturbations. Anyone who clarifies this early can estimate costs and schedule more reliably. The result is a connection concept that clearly brings together the grid connection point, capacity and requirements of the grid operator. During operation, the grid operator may limit active power, for example in the event of immediate danger or grid work necessary for operation. The connection concept states the grid connection point, maximum capacity, point of interconnection, nominal voltage and the method for providing reactive power. The options are a fixed displacement factor cos φ, cos φ(P), a characteristic Q(U) or a fixed reactive power; by default cos φ = 1 applies. A significant change is, for example, the renewal, reinforcement or addition of plant parts; the requirements must then be met for the renewed or added units.
We integrate the PV plant efficiently into an existing energy system and take battery storage into account from the start. How much capacity your grid connection point can take is shown by the load profile analysis for PV plants. The next step is the electrical design for PV plants; routes and transformer stations are covered by the civil engineering concept. For existing wind farms, hybrid park planning for PV plants helps. For wind farms there is the grid concept for wind farms.
