Grid-Connection-Layer

Grid connection layers are used to specify the location and cost of available grid connection points for the project.

Figure 70: Grid Connection

• Easting – the x coordinate of the grid connection point in meters

• Northing – the y coordinate of the grid connection point in meters.

• Cost of connection to grid to be shared – one-time cost of using this grid connection point. This cost is only counted once no matter how many substations connect to it. If it is not used at all then all the costs are ignored.

• Cost of connection for each HV line – this cost gets added for each substation that connects to this grid connection point.

• Cost of connection per MW – additional cost for each MW connected to this grid connection point.

The PPA tab allows users to limit the amount of power that can be exported through this grid connect node.

Figure 71: Grid Connection: PPA Curtailment

Once enabled, this option allows the limiting of the amount of power that can be exported, resulting in a time-series loss. The limit, in kW, can be either fixed or time-varying.

• Fixed – simply input the maximum power that can be output through this grid connect node

• Time-varying – specify the limit, in kW, for every 10-minute period. For simulated time steps falling outside the range specified here, there is no limit. Also, within the specified period, negative values imply no limit.

In order to use the PPA curtailment in the grid connect layer, the cost of energy functionality must be used. This means the user must specify a collector system layer and substation layer but roads can be disabled, in the OCOE settings, and the electrical loss can be fixed in the energy loss settings.

NB: When simulating the collector system loss designed by the OCOE, due to the complexity of interaction between electrical losses and the PPA curtailment, net power can vary a little around the user-defined limit.