Are you aware of the new G99 Regulations?

Are you aware of the new G99 Regulations?

Are you developing a grid connected generation project rated at 0.8kW or above? Engineering Recommendation (EREC) G99 applies to you!

Powersystems are making preparations for the new ENA G99 Engineering Recommendation. Which is coming into effect at the end of April. This will have a significant impact on all new solar, wind, battery, CHP, and diesel generation schemes connecting to the distribution network.

Energy Networks Association (ENA)

Is the voice of the networks. Representing the ‘wires and pipes’ transmission and distribution network operators for gas and electricity in the UK and Ireland.


Was issued in July 2018, by the Energy Networks Association (ENA), following the assimilation of the EU Commission Regulation on harmonising network standards, known as Requirements for Generators (RfG), into GB Distribution and Grid Codes. It has been written to comply fully with RfG as well as including other requirements for connecting into the GB Power System.

It encompasses and replaces the long serving EREC G59 with changes to the application process, compliance requirements and commissioning requirements. G99 generators will need to be aware of the new process and requirements.

Powersystems Staff Training on G99

Powersystems lead Electrical Design Engineer, Ross Falconer, carried out in-house training session with staff this week on G99. G99 replaces Engineering Recommendation G59 and details the requirements for generation equipment connecting to distribution networks.

The new G99 standard has more onerous operating requirements compared to the previous G59 standard, especially for generation schemes that are 1MW or larger. Generators are now required to provide; frequency response, fault ride through, fast fault current injection, voltage control, and variable reactive power; capabilities that were previously handled by large grid code compliant power stations. These new requirements for distribution connected generation schemes will give DNO’s much greater control to actively manage generation within their networks.

Frequency Response Requirements

Generators must now control their active power output in response to frequency changes on the grid. The frequency response requirements are divided into two modes: Limited Frequency Sensitive Mode (LFSM) and Frequency Sensitive Mode (FSM). Limited Frequency Sensitive Mode requires that generators decrease their active power output (MW) if the frequency rises over 50.4Hz, and increase their active power output if the frequency falls below 49.5Hz. Whereas Frequency Sensitive Mode (FSM) is a more onerous requirement for larger generators that requires the installation of a fast acting proportional frequency control device that can respond to frequency changes and can quickly ramp up or ramp down active power by 10%.

Fault-Ride-Through Requirements

Generators over 1MW must now remain connected to the grid when there are significant voltage depressions due to faults on the grid. This is known as fault ride through capability, and helps avoid blackouts occurring on the grid by ensuring that if one generation site trips out due to a fault it does not take out other generation sites along with it. The depth of the voltage depression that a generator must remain stable for varies depending of the generator size, with the largest generators needing to ride through a complete loss of voltage for 140ms.

Fast Fault Current Injection Requirements

Generators over 1MW also need to support the system during a fault by quickly injecting reactive current in order to keep the grid voltage from dropping too low. Again, this capability helps avoid losing further consumers and generation sites during faults by ensuring the grid voltage is kept as high as possible.

Voltage Control Requirements

G99 requires that generators have a voltage control system that can inject or absorb reactive power into the grid to control voltage. The DNO will instruct the generator to operate in one of three modes: Voltage Control; Reactive Power Control; or Power Factor Control.

Reactive Power Capability

The reactive power capability requirements for generators have also been enhanced. For Power Generating Modules between 1MW and 10MW when operating at registered capacity they must be capable of continuous operation between 0.95 lagging to 0.95 leading power factor at the connection point. Generators larger than this have specific reactive power capability windows that they must be able to operate (at all points) within.

Testing Procedures Conform to the latest G99 Protection Settings

The G99 Engineering Recommendation also details revised protection settings for the automatic disconnection of generation in the event of voltage or frequency disturbances on the grid. Our commissioning engineers are updating their G99 testing procedures to ensure all our generation schemes commissioned from May 2019 onwards are tested to the latest G99 protection settings.

Developers and generation equipment suppliers

Developers and generation equipment suppliers need to be aware of the new G99 regulations in order to ensure their products have the capability to meet these higher performance requirements.

Powersystems can assist by designing a site electrical system with appropriate measuring points to allow generator controllers to perform to G99. In some cases, the generating unit will be incapable of meeting the G99 requirements on its own, and it will be necessary to install additional compensation equipment such as reactors, capacitors, or STATCOMs.

Powersystems can identify where this is the case, and design and build electrical infrastructure that works in harmony with generation equipment to fulfil your G99 obligations.

This Engineering Recommendation (EREC) The Purpose

This Engineering Recommendation (EREC) is published by the Energy Networks Association (ENA) and comes into effect on 27 April 2019 for Power Generating Modules first installed on or after that date.

It has been prepared and approved for publication under the authority of the Great Britain Distribution Code Review Panel. Power Generating Modules that fully comply with this EREC G99 can be connected in advance of 27 April 2019 as they also comply with the pre-existing EREC G59 requirements.

The purpose of the Engineering Recommendation (EREC) is to provide requirements for the connection of Power Generating Facilities to the Distribution Networks of licensed Distribution Network Operators (DNOs).

It is intended to address all aspects of the connection process from standards of functionality to site commissioning, such that Customers, Manufacturers and Generators are aware of the requirements that will be made by the local DNO before the Power Generating Facility will be accepted for connection to the Distribution Network.

The guidance given is designed to facilitate the connection of Power Generating Module(s) whilst maintaining the integrity of the Distribution Network, both in terms of safety and supply quality. It applies to all Power Generating Module(s) within the scope of Section 2, irrespective of the type of electrical machine and equipment used to convert any primary energy source into electrical energy.

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Powersystems Staff Up To Date with Current Wiring Regulations

Powersystems Staff Up To Date with Current Wiring Regulations

The 18th Edition brings up to date regulations to the electrical industry

Utilising Powersystems excellent in-house training academy facilities has enabled Powersystems to employ an external training body to deliver the latest 18th Edition wiring regulations course. All the technical installation staff are now compliant with the current BS7671 wiring regulations. Keeping up with the latest standards ensures that we deliver excellent engineering services to all our clients.

This 3 day electrical training course will enable you to gain familiarity with the layout, content and application of BS 7671:2018 – 18th Edition Regulations. This Certificate ensures you are up-to-date with the latest industry regulations on wiring and the safe use and operation of electrical equipment and systems. This course is entirely theory based and is completed by way of an online multiple choice open book exam.

The IET expects the 18th Edition to be live by July 2018, however the design of electrical installations are not required to comply to the 18th Edition until January of 2019. This means until July 2018 you can only take a 17th Edition Wiring regulations course.

EASY PAYMENTSA small deposit secures your place on the course
FLEXIBLE TRAININGChoose to train week days or at the weekends
INTEREST FREE PAYMENTSPay as you train without paying any interest
ACCOMMODATION ON SITEAccommodation available for only £20/night

What You’ll Learn

The 18th edition course is aimed at practicing electricians, electrical contractors and those who require to have a good working knowledge of BS 7671. The aim of this 3 day electrical training course is to gain familiarity with the layout, content and application of the BS 7671: 2018 18th Edition Regulations. It is intended to ensure that on completion of this course, individuals are conversant with the format, content and the application of the Requirements for Electrical Installations BS 7671: 2018 18th Edition Regulations. A basic understanding of electrical principles is recommended in order to be successful on this course.

  • Scope, object and fundamental principles
  • Definitions
  • Assessment of general characteristics
  • Protection for safety
  • Selection and erection of equipment
  • Inspection and testing
  • Special installations or locations
  • Appendices

Changes for 18th Edition are suggested to be as follows:

  • Protection against overvoltages – Clause 443 is likely to be overhauled.
  • Protection against fire – Chapter 42 will be updated with extra information on arc fault detection
  • Electrical Embedded heating – Section 753 will be extended to include embedded electrical heating systems for surface heating, and will include de-icing and frost prevention systems.
  • Energy efficiency – There will be a brand new section covering energy efficiency

Able Skills is an IET Centre of Excellence and we do recommend that if you want to keep abreast of the pending changes and confirmed dates for implementation, you take the time to read BS 7671: the 18th Edition report.

How You’ll Learn

This course is entirely classroom based, it introduces wiring regulations and covers their application through explanation and worked examples. We will ensure that you are fully prepared for the City & Guilds 18th Edition test which is a 2-hour multiple-choice, on-line examination. The exam is ‘open book’, meaning that you will be able to look up wiring regs and refer to the 18th edition book during the exam process.

These are essential to ensure continued safe practice with in the industry, and aids in reassuring clients that correct procedures are followed.




Technical Staff Now up to Date with Current Wiring Regulations

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Important Changes to Getting Connected to the Grid

Important Changes to Getting Connected to the Grid

What the new Electricity (Connection Offer Expenses) Regulation means for consumers

The new legislation The Electricity (Connection Offer Expenses) Regulation 2018 was voted in favor by all of the six major Distribution network operators (DNOs) – UK Power Network, Western Power Distribution, Electricity North West, Northern Power Grid, Scottish Power and SSE Distribution.

The DNO and National Grid Responsibilities

The DNOs across the UK are responsible for carrying electricity from the National Grid to homes, businesses and industrial users across the country via large pylons which look like those pictured above. 

The pylons are operated by the National Grid and carry electricity to local distribution substations/transformers, at which point a DNO takes over facilitating the passage of electricity via low-voltage overhead lines and underground cables to homes, businesses and industrial plants.

New Legislation from 6 April 2018 The Electricity (Connection Offer Expenses) 

Since 6 April, when The Electricity (Connection Offer Expenses) Regulation 2018 came into effect a fee is now chargeable by the DNO for an application for a new electricity connection to cover researching, designing and planning the application.

By way of background the DNOs had received a large increase in connection applications during the past couple of years, for which they carried out the assessment and design for the connection, before issuing the proposal to the end client. A vast amount of these were declined by the end client due to costs and/or the work no longer being required. The research and design phase is technically quite time consuming and having a fee in place will cover their costs.

Each DNO has its own approach in terms of operating within the new regulation and how each new application is handled, but generally efficiency of the connections process should improve and costs will be more evenly allocated because people will think before making an application.

Each DNO will have their own charges, which again will vary from job to job depending on the complexity. This will be on top of the proposal for the connection works and will still be required even if the end-user rejects the offer.

As the assessment and design process can take up to 40 working days from start to finish, make sure you take advice from experts before arranging any connection requirements, as a change of mind later on will have cost implications.

Connection Offer Expenses – New Regulations

BEIS are introducing new regulations which come into force from 6 April 2018, in the form of the Electricity (Connection Offer Expenses) Regulations 2018. This will allow all Distribution Network Operators (DNO’s) to charge customers a fee for assessing their connection offer, regardless of whether they are accepted.

Distribution Network Operators (DNOs) are legally obliged to provide customers with an offer to connect to the electricity distribution network.

Assessment and Design

Expenses are incurred by the DNO’s in reviewing applications, assessing the network, designing the connection and preparing the connection offer, known as the Assessment and Design (A&D) Fee.

In providing connection offers to customers, the DNOs incur Assessment & Design (A&D) costs which typically include the costs of DNO staff wages, undertaking surveys, site visits, drawing plans, accommodation and equipment amongst other things.

Previously, only customers that accept the offer are required to pay the A&D fees. These customers also paid the DNO costs of providing connection offers that are not accepted. In recent years, the number of connection applications and proportion of connection offers not being accepted has grown. This has led to an increase in the DNO resources required to prepare the connection offers and in the costs being spread across those who accept their offers.

Very shortly each DNO will be providing detailed information about the new A&D fees. These will currently apply to HV and EHV distributed generation applications and rates for which will be published within their Connection Charging Methodology and Statement document. This information should then be available on their website.

Applicable Fees

From 6 April 2018, The Department for Business, Energy & Industrial Strategy (BEIS) introduced new regulations that allows DNOs to charge customers for their connection offer whether it is accepted or not. These charges will be applied to 33kV and 132kV connections. DNO’s will then be applying these charges to distributed generation connection applications over 1MVA at 6.6/11kV and they then intended to roll it out further to other connections at a later date.

The new legislation is supported by Ofgem who believe that the upfront fees will allow for a fairer allocation of costs by ensuring that customers who do not accept connection offers contribute to the costs of assessing their applications. It also allows DNOs to work more efficiently and improve the service our applicants receive.

How it Works…….

It’s not clear at this stage whether all DNO’s will follow suit, however SSE have advised that a separate Connection Offer Expense invoice will be issued at the same time as the connection offer. At which point the customer may accept and pay the full connection offer expenses (to secure the connection), or not accept the offer but pay the Connection Offer Expenses Charge invoice. Non payment of the connection offer expense invoice will result in the debt being pursued through a DNO’s normal debt recovery process.

The link to the new regulations can be found on this link –

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