Balancing Grid Code Compliance with Project Efficiencies

In a prior article, we discussed the importance of preplanning for compliance across electricity infrastructure projects [1] from the onset, citing the various risks associated with failure to do so. Yet, we’d be remiss not to acknowledge that while ensuring compliance is of the utmost importance, challenges exist at both ends of the compliance spectrum. In essence, risks exist both within a failure to pre-plan for compliance and also in the over-engineering of electricity infrastructure to a point far beyond the compliance standards laid out in the CDM 2015, EREC G59, EREC G98, EREC G99, EREC G100, and so on.

Taking example in one particular area of where over-engineering is common is that of regulation around electrical cables and the relevant ratings for cable temperature, current, and voltage. Understanding and selecting cable ratings is essential for keeping electrical infrastructure compliant (particularly in the case of BS 7671), influencing not only safety, but also performance and cost. Yet, with cable size and current ratings being intrinsically linked, it’s all too common to see the over-engineering of wires and excess cable size as a means of driving current ratings; this, however, can come with severe implications in terms of material costs and even equipment weight. [2]

So what’s the alternative? Well, that’s where things become a little more complicated. While cable size is intrinsically linked to current ratings, bonding arrangements and the installed environment are actually two of the highest impacting factors in current ratings [3] and, while the installed environment may be difficult to control, bonding arrangements are not. Complications come, however, in understanding the best type of bonding arrangement for a particular installation, with solid bonding, single-point bonding, cross-bonding, and impedance bonding all offering strengths in rather different environments. Ultimately, a bespoke approach must be taken, else efforts to drive down cost may question compliance, or particular bonding arrangements may be excessive and have a similar impact in terms of creating additional cost for equipment and maintenance with little tangible benefit. 

Once again, this is where partnership with a concise knowledge base on all areas of compliance demonstrates its value. While over-compliance can avoid many of the risks associated with non-compliance (including financial penalties and disconnection from the network in particular), it also shares many of the same outcomes in terms of additional project costings and delays far in excess of those required to deliver a compliant solution. As for the solution, the simplest case comes in the form of a single-source solution for electricity infrastructure projects which can consider both the regulatory compliance aspects driven from the consultative side and the on-site practicality of delivering a solution on-time and within budget from the contracting side – in this case, designing in the correct bonding arrangement to suppress CapEx costs from the onset. 

As Joshua Asobi, Managing Director of Green Engineering explains: “Ensuring compliance is of the utmost importance, but it’s similarly important not to over-engineer solutions in a desperate effort to fool-proof your project either. In many of the projects we’ve handled I have first-hand witnessed the duplication of functions within the design and layering on protections on top of protections to the point that solutions are completely over-engineered and inflated in project costings. It’s a fine balancing act to ensure compliance but also deliver projects in a way that is time, cost, and resource efficient, but it’s for that very reason that clients come to Green Engineering as a means of ensuring that balance. We can bring that balance of the theoretical and practical to cover all bases.”

[1] Other Article: Preplanning for Grid Code Compliance

[2] https://uk.rs-online.com/web/content/discovery/ideas-and-advice/cable-ratings-guide 

[3] https://elek.com/articles/sheath-bonding-design-guide-for-hv-cables/