Case Against Remote Filtering For Discussion G54-2 Meeting #3 10 May 2011

Agenda Project Financing For Small to Medium Power Stations O & M Issues for HV Operation

Project Financing for Small and Medium Power stations Current Scenario Project Planning Phase Harmonic studies costly and time consuming so not done until project is definitely a go ahead. Generator data is required for studies. Generator selection and site layout usually late in the planning process. Harmonic studies are therefore carried out during the project delivery phase. Most developers will recognise that there is a risk that the studies will find that filtering is required. These can be included as a risk provision as the cost can be estimated. Project Delivery Phase Should the harmonic studies find that there is a problem during the build phase it is relatively straight forward to alter the substation design to include a suitable filter. The cost of this work can be predicted and is also likely to be included in the planning permissions for the existing installation. Civil and Electrical Contractors will be onsite and so work can be carried out under the existing project CDM program

Project Financing for Small and Medium Power stations Remote Filtering Project Planning Phase The possibility of having to install harmonic filtering remotely could significantly add to the cost of a project. Cost too high to assess and add as risk provision Harmonic studies will therefore have to be carried out earlier in the project phase and may affect feasibility of smaller projects. Planning permission and way leaves may be required to install remote filtering. The project may be consented but permission for the remote filtering refused. Separate connection agreement or legal framework required for remote connection Project Delivery Phase Project harder to manage as it will be split over 2 sites. Data link will be required between remote filter and main power station SCADA for monitoring. This could be costly.

O & M Issues for HV Operation Remote Filtering O&M Phase Remote filtering will be connected to 3rd party HV assets. Access for isolation of remote filter will require presence of the 3rd parties Senior Authorised Person to isolate plant and issue a Permit to Work. Possibility for delay in access for repair work will leave power station non- compliant for longer than would normally be the case for local filter options Remote filtering adds complexity and cost to the development and operation of small to medium power stations