11 Sep 2017

How to ensure offshore construction and commissioning has the power to minimise costs

offshore wind turbine ocean
  • Written By

    Marcus Saul, Renewables Specialist

  • Published in

How to ensure offshore wind commissioning has the power to minimise costs

It may be self-evident that power is an essential part of any renewables construction project. What is not so obvious is how to manage additional specialist power requirements, or what to do when existing power is unreliable or even lost.

Whilst power problems could be a mere hindrance to an onshore renewables site, (resulting in perhaps a day’s loss of work) they have the potential to become a bill running into £1000’s in harsher offshore environments - through delayed costs, legal claims, missed generation revenue and the possibility of voiding turbine warranties.

Electricity’s ubiquity and utility can be a curse, often being left to last on a list of important things to consider during the planning process. By engaging with companies, such as Aggreko, before the start of a project, effective power design solutions can be developed. These can help reduce costs due to reduced ‘downtime’, as well as mitigate risk by testing applications, such as offshore substations, prior to being ‘floated-out’.

So when considering the critical path for your project an allowance needs to be made for your comprehensive power needs. Below are some of the things to remember:


Whether it is a generator at the base of a turbine to assist with preservation and commissioning or a high voltage (HV) energisation package, it is important to consider if your chosen provider has the ability to scale your requirement. What may be a short-term ‘one-off’ generator hire can snowball into a full-scale, unforeseen demand for site-wide power. In such a situation the ability of your power supplier to rapidly and reliably scale your project is critical.

Aggreko’s experience in offshore project management and fleet co-ordination means that we can provide generators for a multitude of applications – from the simple to the most complex.

But physical assets are only part of the equation. Aggreko has highly trained engineers, who are able to address challenging technical situations for harsh environments. And as with all successful teams, they are backed by a support network of designers, engineers, mechanical and electrical specialists, all focused on achieving that first principle, at no extra cost to our customers.


The dynamic nature of offshore projects requires flexibility and from a power perspective, the need for your supplier to respond quickly and efficiently to your project’s needs. With multiple locations and an extensive workforce and fleet, Aggreko is flexible enough to reallocate equipment and knowledge from project to project as required, without increased cost to our customers.

By choosing a supplier who delivers a turn-key solution, you will take all the stress out of managing your site power, servicing and maintenance, refuelling and associated staffing and inventory, so you are able to focus on your core business.


Crucial for any power generation requirement is the generator’s reliability. A simple question to ask is whether your generator has been designed and tested specifically for the offshore market? There are a number of issues to consider, from the correct bunding of a generator’s fuel tank to prevent fuel spillages, through to engineered weather protection to ensure optimal running throughout the year.

If equipment has not been chosen with such considerations in mind, this can result in serious delays, both for the construction and commissioning phase. Aggreko’s uniqueness comes from our ability to learn from each project we come up against and develop and test our technology to meet each specific challenge. Because we only manufacture generators for ourselves, we are able to constantly improve and hone our generators to suit the application.


There are two main options available to offshore construction and commissioning managers: purchase or hire. Both options have their pros and cons. When purchasing, the initial price isn’t always what you end up paying. There are often additional costs to consider, such as ongoing servicing and parts, both of which can mount up.

In addition, if there is a ‘catastrophic’ failure of power, you should consider whether you are entitled to claim any of the damage under your purchase warranty. As standard generators are not designed to work in harsh offshore environments, they may not be covered. With rental options, all service and maintenance work is included in the price and the unit will be replaced as fast as operationally possible should a problem occur, allowing our customers to focus on their project’s objectives.

Aggreko’s commitment to assisting in reducing project costs has seen the introduction of dynamic load sharing generators that can extend intervals between services by switching loads, as well as minimising fuel consumption. What is more, our range of lightweight generators, designed for the offshore environment, has enabled our customers to use crew transfer vessels (CTVs) for the installation and removal of generators, avoiding a more costly vessel option, which may be in excess of £40,000 per day to hire.

Time is money, and so in a challenging environment, and where every minute costs, you need to ensure you have the power to make, every minute count.