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Greener Upgrades blog series #1

Rightsizing power packages

How to rightsize a power package

Rightsizing a temporary power package is a crucial aspect of optimising power provision for a site or project. It involves matching the power generation capacity with the specific power demands, aiming to create efficiency gains. Regardless of industry or how small or large the power requirement, rightsizing is essential to minimising fuel use, emissions, and maximising efficiency. This blog explores what rightsizing is and how it can be implemented into power projects. 

What is rightsizing?

Rightsizing is the process of matching the power demand of a project with the appropriate generator or utility package. It involves understanding the exact power requirements of the project and aligning the power provision with the demand. This concept can be applied to most industries, from data centres and construction to manufacturing and utilities.

Benefits of rightsizing

Increased efficiency

Lower emissions with right sizing

Lower emissions

Reduced fuel usage

Lower fuel costs

Common reasons for oversized generator packages

Oversizing generators can impact operations in a number of ways. Generators do not perform well at low loads, leading to inefficiency, performance issues, fuel wastage, and potential breakdowns. Inefficiency can also lead to additional emissions and pollutants.  So why are generators often oversized? The most common reasons are:

  • Motor start machinery
  • Adding resilience
  • Peaks or fluctuations in demand
  • Lack of knowledge about required power load
  • Lack of foresight regarding project demands
  • A need for spinning reserve or redundancy

How to rightsize a power package

Right sizing a power package

• Clearly define power needs, whether for the entire site or specific equipment
• Consider the potential for changing power needs during the project

• Analyse the site or equipment’s load profile, including peak demands, low demand, and base loads
• Identify timing and patterns of power fluctuations

• Identify equipment with high inrush currents and specific periods of operation
• If powering equipment, gather information about power needs i.e. start up or running currents


• If available, historical power consumption data can offer insights into past usage patterns and predict future demands.

• Emissions regulations: is there any regulatory or legal requirements for the project in relation to emissions?
• Noise requirements: are periods of low noise required? 
• Power criticality: how critical is the project, is full or partial resilience a requirement?
• Events: are there any planned and unplanned events affecting power requirements?

Options for rightsizing power generation packages

1. Downsizing the generator

  • This involves reducing the size of the generator if we have established through load profile analysis that this is possible
  • To further optimise efficiencies consider upgrading to a more fuel-efficient and lower-emission generator for example upgrading from Stage 3a to Stage V generator)

2. Load on demand

  • In a load on demand package, instead of one large generator we use multiple smaller generators that automatically scale power up or down according to demand
  • Using sophisticated control systems, when a load reduces, and a generator is not required it will automatically turn off to improve fuel efficiency and reduce emissions, this ensures that the generators that are still running, operate at optimal load
  • Standby generators can be added to a load on demand package to add additional resilience, only running when there is a disruption to the power supply or during servicing of the other generator
  • We can incorporate BESS (Battery Energy Storage System) to further increase efficiency drive down emissions

 3. Incorporating Battery Energy Storage Systems (BESS)

  • Incorporating battery energy storage into a power package can help avoid long periods of low loading a generator, it can also help by providing power assistance to high inrushes caused by motor starts or high start up currents
  • By supporting high or low loads, the generator can be correctly sized to the base load requirements
  • BESS can in some cases replace or reduce the need for generators in projects with limited grid availability
  • BESS can be integrated into a load on demand package to reduce generator run times and help with a seamless start up
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