Switch supervisor - less consumption, more stability

However, energy-intensive companies have a special responsibility to use all forms of energy in a sensible way. A system referred to as ‘load management’ determines when and how much electricity flows from the grid into GEALAN’s machinery and lines. It monitors and controls energy consumption. Holger Thoß is the brain behind this load management system. He manages the Technical Services and is GEALAN’s Energy Officer. His work is guided by three principles: sustainability – conservation of resources and infrastructure – cost-effectiveness.

“We operate in a grid-friendly fashion”, says Holger Thoß, “because we try to buy electricity as consistently as possible”. Trying is an understatement – GEALAN is committed to this and, in the course of its digitalisation, has installed a system that compensates for fluctuations and warns of impending peaks. “Electricity consumption is documented on a quarter-hourly basis. If it becomes clear that we will exceed a defined consumption limit within a quarter of an hour, the load management system responds”. It doesn’t suddenly go quiet and dark in Tanna – interventions are well-considered and don’t affect production. For example, we can switch off a material mixing line for a few minutes or delay the start-up of an extruder after a setup break. Thoß depends on help from the departments because every measure must be coordinated. The specified quarter-hour limit does not apply on a random or average basis – it applies to all 35,040 quarter hours in a year. If the energy supplier detects excessive consumption in just one of these quarter-hour periods, GEALAN loses several hundred thousand euros in grid fee bonuses.

30 million kilowatt hours

Planning and flexibility must complement one another: “It’s difficult in January to accurately forecast consumption for the whole year. In years like 2020, you can be way off. But we’ve gained experience in this regard. Software-based planning tools help us to estimate power consumption very accurately. In seven years of load management, we’ve only once failed to meet the bonus criteria when we deliberately waived a refund because we had an extremely large number of orders”. Through clever load management, GEALAN compensates for a locational disadvantage: in Germany, a kilowatt hour of electricity costs two to three times as much as in France or Poland. “With an annual consumption of 30 million kilowatt hours, we rely on our grid fee bonus. The grid operator rewards the fact that our consumption is a predictable quantity”

Energy is GEALAN’s fourth largest cost item, after materials and natural resources costs, staff costs and logistics costs. Electricity is the main form of energy – universally usable, readily available, easy to transport, though expensive. So using as little of it as possible is in the company’s interest. “GEALAN has been certified according to ISO 50001 since 2013. This standard defines criteria for systematic energy management. Annual audits are conducted check our measures and evaluate our results”. Fifteen years ago, GEALAN used almost 60 percent more electricity to extrude one tonne of PVC than it does today, although power-intensive start-up processes have become more frequent – as there are more product variants and orders are divided into smaller sections. Holger Thoß: “We’ve invested a lot in the power-saving generation of compressed air and refrigeration, and halved our consumption. We’ve changed our lighting over to LED, equipped extruders with more efficient drives and controls, insulated pipelines and made greater use of waste heat: a recovery system converts extrusion heat into heating energy for Logistics. We’ve taken major steps to save power – now we’re taking care of the smaller stuff as well.

Renewable energy not easily possible

Up to now, GEALAN hasn’t produced any power itself, although this seems so obvious. It is certainly being considered, though the technical and bureaucratic hurdles are high, says Thoß: “Our calculation for a small wind turbine, for example, showed that it wouldn’t be economical for us. A larger wind turbine would have a more favourable cost-benefit ratio, but the land area we would need for it has already been allocated. The planning and approval procedures for wind turbines are lengthy and the locals have reservations. The current building regulations specify roof loads for photovoltaic constructions for which our roofs are not designed”. Nevertheless, GEALAN is clearly committed to the energy transition: “We only purchase electricity from renewable energy sources”.

When Holger Thoß joined GEALAN in 2008, there wasn’t even a permanent electrician to ponder all of the energy and technology issues that were becoming ever more pressing. “It was a nice challenge to create new structures – using my creativity and initiative. My goal was to modernise, to automate the electrical engineering, the operating and plant technology”. Today, GEALAN employs its own electricians and service providers. If a malfunction occurs, an early warning radar set up by Thoß sends an alarm to the technicians’ mobile phones so that problems can be rectified before they cause any damage. “The system monitors and visualises the status of all critical lines. It has become a very important tool for us because it initiates maintenance in time and because it captures valuable data. We’re learning how to control systems even more intelligently”.

Every quarter of an hour counts! Every 15 minutes, a new time period begins in which the load management system monitors GEALAN’s electricity consumption and warns when consumption approaches a defined limit.

Double redundancy instead of Plan B

In the past, failures of the internal water or refrigeration supply have repeatedly had a serious impact on production. For some years now, however, these breakdowns have been practically non-existent because the building management system always keeps an eye on even inaccessible system components. If the BMS reports a serious malfunction, Thoß switches to a redundant system – for years now, doubly installing functionally relevant components for backup purposes has been included in all investments. “Stable production requires less energy, causes less waste and is simply more economical. And ultimately, we can supply our customers with top-quality goods more quickly”

GEALAN produces around the clock in Tanna, from the beginning of January to mid-December. This leaves little opportunity for maintenance. Thoß has to make the best possible use of the narrow time window around Christmas; to plan precisely, he accesses data provided by the building control system.

“Even if something new doesn’t immediately work the way we thought it would: we continue to work on automation, on energy saving, on the stability of our systems. And on making a contribution to good working conditions. Modernisation cuts down on noise and dust and creates comfortable temperatures. That goes down well with our colleagues in production – a significant aspect”.

Holger Thoß manages 40 lines with 100 large drives and 16 different machine control systems. Not every idea he develops can be realised overnight, but “GEALAN has set the right course. Energy efficiency and digitalisation remain big issues that keep me entertained. I look forward to the tasks that the future has in store for me. We haven’t reached our goal yet, but what we have achieved is something to be proud of”.