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NERSA Small-Scale Embedded Generation: Regulatory Rules Consultation Paper highlights


I’m a bit late on this one as the comments were due by the 25th March and the public hearing was on the 10th April, but below is a summary of what’s in the NERSA consultation paper on small scale embedded generation regulatory rules, published at the end of Feb 2015.

The document seeks to establish the principles upon which small scale (primarily solar PV) generators can operate, and the tariff structures that will apply.  It also supersedes the standard conditions for embedded generation within munics document that was issued in 2011, as this only considered systems of up to 100kW (quite small).

The paper seeks to:

  1. solicit comments from stakeholders on the proposed regulatory rules for small-scale embedded generation; and
  2. explore various tariff options available in promoting and incentivising installations that are grid-tied


Registration versus licensing:

Recognising the administrative burden associated with applying for a generation licence, as required under the Electricity Act, the paper recommends that all systems under 1MW are registered with the local distributor instead.

Various information is required for each system, including “technical studies and report on how much the network can take on these installations.”  The viability of this requirement for each individual system should probably be considered, and I suspect what they’re after here is that the munic or distributor should have a good and thorough understanding of the network’s capacity to embed generators within their system.

Reporting requirements:

The munics or distributors are required to report various information on an annual basis to NERSA.

Grid interconnection standards:

While the NRS 097 series is not complete and do not cover all technical aspects relevant for grid connection of SSEG systems, all systems are to be compliance with NRS 097-2-1:2010 and NRS 097-2-3:2014.


NERSA has requested comment on the suitability of type testing on inverters used for SSEG systems, in the absence of a SANS certification or inverter standards.

Codes of practice:

NERSA provides a high level outline of how they would approach the following technical requirements, and asks for comments from stakeholders accordingly:

  • Grid connection requirements
  • Power quality and limits of liability
  • Technical performance
  • Information exchange protocols
  • Signals, Communication and Control Functions


The meaty bit of the document in my opinion.  The principles outlined in this doc are pretty similar to those explained in my previous post (found here)

They separate the tariff out into two main types:

Charges for consumption:

  • Fixed costs based on the installed capacity; and
  • Energy cost at a set tariff for net-import OR a time of use tariff

Revenue for generation:

  • Export credit for any net export of electricity.

This export credit will be equivalent to the avoided energy generation costs only, which for munics will be the marginal charge for electricity purchased from Eskom, or for Eskom, will be equivalent to the cost of generating electricity.

This is to avoid impacting any customers who are not listed as SSEG’s (again, see my previous post on this).

This means that NERSA is not proposing a net-metering structure where consumption and generation is weighted evenly in terms of energy cost, despite the fact that the term net-metering is used in the paper.