Retrofitting Automation into Older Factories: Where to Begin

As UK manufacturers adapt to the changing demands of production, factory automation is becoming essential, not just for new high-tech facilities, but for older, established sites too. Many mid-sized and large manufacturers operating in legacy buildings are turning to automation to increase productivity, lower costs, and deal with staffing challenges. However, adding automation to an older factory can seem like a big task.

Retrofitting automation into an existing plant presents a unique set of challenges. Success depends on smart planning, a solid understanding of your current infrastructure, and the ability to carry out upgrades without disrupting daily operations. In this article, we explore how manufacturers can begin the process, with insights from AES, experts in automation and electrical contracting for UK industry.

Why Automate in Older Factories?

Automation offers measurable benefits for manufacturers, especially during times of rising energy costs, labour shortages, and growing pressure to hit sustainability targets. For companies in sectors such as food production, plastics, construction materials and textiles, automation can help address a range of operational pain points.

For example, it can:

• Reduce manual labour in repetitive or strenuous tasks
• Improve product consistency and reduce errors
• Provide better data for performance tracking
• Enhance workplace safety
• Support predictive maintenance and proactive fault detection

Thanks to more flexible, modular, and cost-effective automation solutions, older facilities can now adopt smart technologies without a complete overhaul.

Begin with a Thorough Site Assessment

Before introducing any new systems or equipment, it's important to understand your current setup. A full site assessment will highlight strengths, weaknesses, and potential risks and help shape a plan that fits your goals and budget.

Key areas to review include:

• Condition of electrical distribution panels, wiring, and circuits
• Existing programmable logic controllers (PLCs) or basic relay-based systems
• Equipment age and reliability data
• Safety systems and procedures
• How operators currently work and how digitally prepared the site is

At AES, we conduct in-depth evaluations to identify where automation will make the biggest impact—and how to implement it without affecting ongoing production.

Focus on Practical Starting Points

Automation upgrades can be done gradually. In fact, a phased approach is often the most effective, especially in live manufacturing environments. We recommend starting with areas that offer quick wins.

These could include:

• Conveyor systems, packaging lines or robotic palletisers
• Simple sensors to monitor flow, temperature or pressure
• Replacing outdated control logic with a modern PLC
• Introducing variable speed drives on motors and pumps
• Automating batch control for more consistent product output

Many of these changes can be made while your plant remains in operation, with minimal downtime or disruption.

Upgrade Control Systems with Long-Term Goals in Mind

One of the most important parts of an automation retrofit is the control system. Many older factories still rely on out-of-date PLCs or manual switchboards with limited capability. Upgrading to a modern control system provides more than just improved machine logic—it opens the door to advanced diagnostics, energy monitoring, and remote access.

When AES designs control upgrades, we prioritise scalability. That means choosing systems that can grow as your needs change, avoiding systems that lock you into one vendor, and using open standards for smooth integration across future projects.

Don’t Overlook Network Infrastructure

Today’s automated factories are built on data. From sensors and drives to control units and analytics tools, everything relies on fast, reliable communication.

If your factory was built decades ago, it likely doesn’t have the network infrastructure to support modern automation. Key steps might include:

• Installing industrial Ethernet or reliable fieldbus networks
• Creating a separate control network from your office IT systems
• Adding switches, routers and PCs for interface displays and data storage

AES can also help you link your systems to cloud platforms for centralised dashboards and remote alerts, if that fits your business model.

Make Safety Part of the Plan

Introducing automation changes how operators and machines interact, so safety must be considered from the start. In older sites, retrofitting safety systems is often part of the upgrade process.

This might involve:

• Adding light curtains, interlocks or emergency stops
• Updating control panels to include safety-rated features like Safe Torque Off (STO)
• Conducting risk assessments to meet UK safety standards for machinery

In many cases, automation actually improves safety, by keeping workers away from hazardous tasks or standardising how equipment is shut down.

Assess Electrical Capacity Before Adding Load

Automation typically increases electrical demand. New sensors, actuators, drives, and control units all draw power, and many older factories operate close to their existing electrical limits.

Before beginning, it’s important to assess whether your facility has enough capacity. AES provides full load assessments and can recommend whether energy efficiency measures (like LED lighting or power factor correction) can free up headroom for automation.

Where necessary, we can also plan for staged upgrades that align with both budgets and production schedules.

Choose the Right Partner for Legacy Environments

Installing automation into an older, working factory is very different from designing a system for a brand-new facility. It requires technical skill, hands-on experience, and respect for the realities of an operational site.

AES has delivered retrofit automation projects for manufacturers across the UK, with a clear understanding of how to work around production, minimise downtime, and deliver systems that generate fast payback.

Our approach involves close collaboration with your in-house teams—so the final system meets your technical, operational and safety requirements.

Conclusion: Build Automation Into What You Already Have

You don’t need a brand-new building to embrace automation. In fact, some of the most effective improvements are made in older factories—where experience, equipment and infrastructure already exist.

The key is to take a measured, well-planned approach. Assess your site, prioritise value-led upgrades, and partner with professionals who understand legacy systems.

Whether it’s adding sensors, upgrading control panels or automating packaging tasks, each improvement strengthens your operation and prepares you for future challenges.

Interested in starting your automation journey? Contact AES to book a site assessment and begin planning upgrades that work for your factory today—and tomorrow.