For plant managers, energy managers, and maintenance engineers: this article explains how industrial regenerative braking and braking resistor energy recovery retrofits work, what is genuinely new about IR Power’s reducERS approach, and what constraints, risks, and verification steps to expect in the real world.
Introduction
Factories waste electricity every time heavy rotating equipment slows down. With many variable-speed applications, a motor becomes a generator during deceleration and sends energy back onto the DC bus (direct-current link) inside the drive. If that energy cannot be reused immediately, it is typically burned off as heat in braking resistors (also called dynamic braking resistors).
IR Power (a Scottish company within the MWNW Group) has developed reducERS, a retrofit system intended to capture that “braking resistor” energy and reuse it on-site. The company positions reducERS as a modular, plug-and-play industrial energy recovery solution with a pay-for-performance commercial model.
Important scope note: when you see figures like “around 10–20% savings,” these are best interpreted as reductions on the electricity consumption of specific assets or machine groups (for example, a press cluster), not the whole facility. Actual results depend heavily on duty cycle, braking intensity, and what regeneration capability you already have installed.
TL;DR: reducERS targets wasted braking energy at the machine level; savings are asset-specific and strongly dependent on the load profile and existing drive setup.
How braking energy is created (and why it is usually wasted)
In many industrial machines—presses, centrifuges, test rigs, high-inertia conveyors, hoists, and winders—motors repeatedly accelerate and decelerate. During deceleration, kinetic energy from the load is converted into electrical energy by the motor and pushed onto the DC bus of a VFD (variable frequency drive, also called a VSD—variable speed drive).
There are three common outcomes for that regenerated energy:
- Dump to heat (most common): a braking chopper (a switching device in the drive) sends energy to resistors, converting it to heat.
- Regenerate to the AC supply: a regenerative drive/front-end converts DC bus energy back to AC and exports it upstream (subject to electrical design and compliance).
- Share locally: DC bus sharing allows multiple drives to exchange energy on a common DC link so braking energy from one axis can feed another axis that is motoring.
Braking resistor energy recovery is attractive because it targets a known, measurable loss mechanism: heat dumped into resistors. However, it is not “free energy”—the recoverable amount is bounded by the mechanical energy you dissipate, the electrical conversion efficiency, and whether there is a place to use or store the energy at the moment it is generated.
TL;DR: motors regenerate during decel; without a path to reuse or export energy, most plants dump it as heat through braking resistors.
How IR Power’s reducERS claims to work (and what to ask technically)
IR Power describes reducERS as connecting to a machine’s braking circuit—effectively the “electrical exhaust”—to capture energy that would otherwise go into braking resistors. The system then makes that energy available for reuse by the host machine or elsewhere on the site.
At a practical engineering level, any solution in this category typically needs four building blocks:
- Power electronics interface to accept DC energy from the braking circuit safely and within voltage/current limits.
- Energy buffer/storage to handle fast transients (milliseconds to seconds) and mismatches between generation and reuse.
- Inverter or DC/DC conversion to deliver usable power back to a DC bus or into an AC network.
- Protection & control (over-voltage, over-current, thermal protection, isolation/earthing approach, and fail-safe behaviour).
Energy storage clarification (critical): most industrial “regenerative buffering” systems use a mix of DC bus capacitors (for very fast response) and either larger capacitor banks, ultracapacitors (also called supercapacitors), or batteries for longer buffering. Capacitor-based storage responds very quickly and handles high peak power well, but has limited energy capacity; batteries store more energy but generally have slower peak response, finite cycle life, and stronger temperature/maintenance constraints. If reducERS relies primarily on capacitors/supercapacitors, expect excellent response time and high cycle life; if it uses batteries, expect higher energy capacity but more lifecycle management (health monitoring, replacement planning, and stricter safety design).
Indicative electrical ranges (what to confirm during a survey): most modern low-voltage VFD DC buses sit roughly around 540–650 VDC for 400 VAC-class drives; medium-voltage drives can be substantially higher and are a different integration class. Ask IR Power which voltage classes are supported and whether the system interfaces at the braking resistor terminals, the DC bus, or via a dedicated regen port.
Round-trip efficiency (indicative): in many conversion-and-buffering architectures, a realistic expectation is that not all captured energy is returned—losses occur in switching devices, magnetics, and storage. A credible system-level round-trip efficiency often falls in the high-80s to mid-90s percent range, depending on topology and loading. Any proposal should state assumptions and provide measured data.
Compatibility (what “works with any drive” really means): most retrofits can coexist with common VFDs (ABB, Siemens, Danfoss, Schneider Electric, Yaskawa, Rockwell, etc.) if they interface in a vendor-neutral way at braking resistor circuits. But “compatible” does not always mean “zero engineering”: expect checks on braking transistor ratings, resistor sizing, cable lengths, EMC (electromagnetic compatibility), and how braking commands are handled in the control architecture (PLC—programmable logic controller—logic, drive parameters, safety circuits).
TL;DR: reducERS sits where braking energy is normally burned off; the real differentiator depends on its storage topology, supported DC bus classes, measured efficiency, and how “vendor-neutral” the interface truly is.
What’s genuinely new vs established regenerative technology
Regeneration itself is not new. Plants have used regenerative drives and DC bus sharing for decades. The key question is whether reducERS changes the economics and adoption friction rather than inventing a new physics principle.
1) Traditional regenerative drives (active front end / regen units)
These export energy back to the AC supply through a controlled rectifier/inverter stage. They can reduce resistor heating and improve energy performance, but typically involve higher capital cost, more engineering effort, and sometimes more stringent harmonic/power-quality design. Depending on the front-end design, you may need line reactors/filters and careful compliance work.
2) DC bus sharing (common DC link)
This is very effective in multi-axis systems where one axis brakes while another motors (e.g., cranes, coordinated lines). The limitation is that it is easiest when designed in from the start or when multiple drives are already on a common bus. Retrofitting bus sharing across heterogeneous OEM equipment can be complex.
3) Braking resistor energy recovery retrofits (the “in-between” approach)
These capture energy that would otherwise be dissipated and reuse it locally, often with less disturbance to existing drive line-ups than a full regen front end. The constraint is that you still need a sink/source match or sufficient buffering; if there’s nowhere to use energy, you end up back at the resistor.
What reducERS appears to add (based on IR Power’s positioning):
- Standardisation: a limited set of product sizes rather than one-off engineered builds can reduce lead time and integration cost (if the sizing truly covers typical press/mixer/conveyor braking duties).
- Integration simplicity: a “connect to the braking circuit” approach can be operationally attractive where replacing drives is unrealistic.
- Business model: pay-for-performance rental can shift risk away from the factory—if measurement and verification are rigorous and transparent.
What is not new: the underlying regenerative braking principle and power-electronic conversion are established. Engineers should evaluate reducERS primarily on proven installation simplicity, measured performance, compliance documentation, and lifecycle costs.
TL;DR: the novelty is less about regeneration and more about packaging, standardisation, and commercial delivery—while the core energy-recovery concept is well established.
How much energy can be recovered (and how to interpret savings claims)
In high-cycling applications such as press lines (fast strokes, high inertia) there can be a steady stream of braking energy. But the recoverable fraction depends on:
- Duty cycle and inertia: more frequent decel events and higher inertial loads increase opportunity.
- Baseline system: if you already have regenerative drives, common DC bus, or well-optimised motion profiles, incremental gains may be smaller.
- Utilisation: two identical machines can have different savings based on throughput, downtime, and recipe variability.
- Ability to reuse energy: if the recovered energy cannot be consumed quickly (or buffered), it will still be diverted to resistors.
As a reality check, it is usually more defensible to talk about a range with scenarios rather than a single headline. For example:
- Moderate braking profile: single-digit to low-teens percentage reduction in the asset’s electricity use.
- Heavy cyclic braking profile (press clusters, high inertia): low-teens to around one-fifth reduction in the asset’s electricity use.
For context on industrial energy efficiency and decarbonisation drivers, the UK government provides guidance and support routes via its energy efficiency and net zero resources (see UK Government guidance on energy-saving opportunities in business and industry).
TL;DR: savings apply to specific machines, not whole sites, and vary with duty cycle, baseline regen capability, and how often recovered energy can be reused.
Indicative technical parameters engineers will want (and should request)
Because IR Power markets reducERS as “standard product sizes,” it helps to anchor expectations with indicative ranges typically seen in industrial retrofits. Exact values should come from IR Power’s datasheets and a site survey, but engineers generally evaluate:
- Drive/motor power range per unit size: many retrofit solutions naturally align to common VFD frame sizes (for example, tens of kW up to a few hundred kW per machine). Press clusters may aggregate to several hundred kW or more across multiple axes.
- DC bus voltage class: typically ~600 VDC class for 400 VAC drives; medium-voltage solutions require different insulation/clearance and compliance approaches.
- Peak vs continuous braking power: braking is often peaky; ensure the recovery system can handle peak kW without over-voltage trips and can also sustain repetitive cycling.
- Round-trip efficiency: ask for measured system-level data (capture → store/buffer → reuse). Efficiency varies with loading and storage choice.
- Compatible architectures: confirm whether it supports single drives, multi-drive cells, and whether it interfaces with resistor terminals, DC link, or both.
- Control & communications: options like Modbus TCP, PROFINET, EtherNet/IP, OPC UA (Open Platform Communications Unified Architecture) matter if you want SCADA/EMS integration.
For background on VFDs and their role in industrial energy use, see the U.S. Department of Energy overview of adjustable speed drives (ASDs) / VFD concepts (note terminology differences by region): U.S. DOE – Adjustable Speed Drives (ASDs).
TL;DR: request concrete specs: supported DC bus class, peak/continuous braking kW, efficiency curves, interface point, and communications options.
Power quality, harmonics, and interaction with site electrical systems
Any device that converts and redistributes energy can affect power quality. Key considerations include:
- Harmonics: if energy is returned to the AC network, the topology (e.g., active inverter) influences current harmonics. Plants may have harmonic limits driven by standards or utility requirements.
- Power factor: some regen/front-end solutions can control power factor; others may behave neutrally. Clarify expected power factor behaviour at different operating points.
- Interaction with PFC and UPS: if you have power-factor correction (PFC) capacitors, active harmonic filters, or an uninterruptible power supply (UPS), verify that the recovery system does not cause control interactions or nuisance trips.
- EMC compliance: switching converters can introduce conducted and radiated emissions; cable routing, shielding, and filters may be required.
Engineers often reference the IEC 61000 family for EMC and power quality considerations; an accessible overview is available from the IEC (International Electrotechnical Commission) webstore (note: detailed standards are typically paid documents).
TL;DR: confirm harmonic, power-factor, and EMC behaviour—especially if recovered energy is shared site-wide or exported into an AC network.
Safety, compliance, and retrofit standards (CE/UKCA, braking circuits, functional safety)
Retrofitting into braking circuits touches safety-relevant behaviour: braking performance, over-voltage protection, and safe torque off (STO) interactions. At minimum, projects typically need:
- CE marking / UKCA marking compliance for the added equipment, including appropriate technical files and declarations (depending on where installed and how supplied).
- Electrical safety and insulation coordination appropriate to the voltage class and fault levels.
- Functional safety review where braking contributes to a safety function (for example, ensuring STO behaviour and that the retrofit cannot prevent intended stopping). Functional safety is commonly framed using IEC 61508 (general) and IEC 61800-5-2 (drives safety functions) depending on architecture.
- Machine risk assessment updates for the modified system, including lockout/tagout (LOTO) procedures and maintenance access.
Because standards selection depends on the machine type and jurisdiction, treat this as an engineering workstream—not a paperwork afterthought. For a starting point on CE marking, see the European Commission’s overview: European Commission – CE marking.
TL;DR: braking-circuit retrofits must be treated as safety-relevant changes; expect CE/UKCA, EMC, and functional safety considerations to be part of the project scope.
Measurement & verification (how “pay-for-performance” should be proven)
A performance-linked rental model can be credible, but only if savings are measured transparently. Best practice usually includes:
- Baseline establishment: log energy and operating context (throughput, recipe, cycle rate) over a representative period before installation.
- Independent metering: revenue-grade or industrial-grade submeters on the target assets and, where relevant, the recovery system outputs.
- Normalisation: adjust for production volume changes so “savings” are not simply reduced output.
- Protocol-based approach: align to a recognised method such as IPMVP (International Performance Measurement and Verification Protocol). Learn more at the official site: EVO – IPMVP.
If a vendor says “no savings, no pay,” ask exactly which meter(s) define savings, who owns the data, how disputes are handled, and what happens if production patterns change significantly.
TL;DR: pay-for-performance is only as strong as the metering plan—use independent measurement, a solid baseline, and IPMVP-style normalisation.
Hypothetical case study: press line energy recovery calculation
Below is a simplified, illustrative example for a press line cluster. It is not a guarantee—real results depend on cycle profile, existing regenerative capability, and how consistently the line runs.
- Installed VFD-driven power (cluster): 600 kW (multiple presses/axes)
- Operating hours: 4,000 hours/year
- Average electrical demand while running: 420 kW (not all installed power is used continuously)
- Electricity price: £120/MWh (i.e., £0.12/kWh)
- Asset-level reduction from braking resistor energy recovery (scenario): 12% of the cluster’s electricity use
Step 1: Annual energy consumption (before)
420 kW × 4,000 h = 1,680,000 kWh/year (1,680 MWh/year)
Step 2: Annual energy saved
12% × 1,680 MWh = 201.6 MWh/year (201,600 kWh/year)
Step 3: Annual cost reduction
201.6 MWh × £120/MWh = £24,192/year
How this maps to a rental model
If the provider charges, for example, 60–80% of verified savings as a service fee during the contract term (rates vary widely), the site might retain ~20–40% of savings immediately while avoiding capex. After the contract term, retained savings could increase depending on the agreement and any ongoing service costs.
TL;DR: in a plausible press-cluster scenario, recovered braking energy could save on the order of ~200 MWh/year and ~£20k–£30k/year at £120/MWh—asset profile and contract share determine the net benefit.
Key constraints and “not ideal” scenarios
Industrial regenerative braking retrofits work best when the machine frequently dumps meaningful energy into resistors and there’s a consistent opportunity to reuse it. Common constraints include:
- Low braking duty: if deceleration events are rare or gentle, there simply isn’t much energy to harvest.
- Already-regenerative systems: if the line already uses regenerative drives or an active front end, incremental benefit may be limited to buffering/optimisation rather than large savings.
- Existing DC bus sharing: plants with well-designed common DC links may already be capturing much of the opportunity.
- Power-quality-sensitive sites: facilities with tight harmonic limits, sensitive instrumentation, or constrained utility connections may require additional filtering and engineering validation.
- Space and heat management: while energy recovery reduces resistor heating, the added electronics still generate heat and require panel space, ventilation, and access.
TL;DR: the best candidates have frequent, high-energy braking; the weakest candidates already regenerate effectively or have minimal braking energy to recover.
Maintenance, reliability, and monitoring expectations
Retrofit energy recovery systems are power-electronic assets; reliability hinges on thermal management, component quality, and operating environment (dust, vibration, ambient temperature).
Ask for (and expect) clarity on:
- Service intervals: periodic inspection of connections, filters/fans, and thermal performance; many industrial panels follow annual/biannual inspection routines depending on environment.
- Wear components: capacitors (life depends strongly on temperature and ripple current), contactors/relays (if used), fans, and any battery modules (if present).
- Alarms and diagnostics: DC bus over-voltage events, temperature derating, storage health (especially for ultracapacitors/batteries), and event logs.
- Remote monitoring: if cloud connectivity is offered, confirm what data is exported, sampling rates, retention, and how outages are handled.
TL;DR: treat reducERS like other industrial power electronics—plan for inspections, understand capacitor/fan lifetimes, and use diagnostics to avoid nuisance trips and performance drift.
Implementation process: from survey to verified savings
A realistic VSD/VFD energy efficiency retrofit project usually follows a structured process:
- Site survey: identify candidate machines, access points to braking resistors/DC links, panel space, and cable routes.
- Data logging: measure braking events, resistor duty, energy consumption, and production context to build a baseline.
- Engineering design: integration drawings, protection coordination, EMC plan, and safety/risk assessment updates.
- Installation: typically during planned downtime; may require MCC (motor control centre) work, isolations, and cable pulls.
- Commissioning: verify braking performance, fail-safe behaviour (fallback to resistors), and alarm handling.
- Performance verification: confirm savings against baseline using agreed M&V rules and reporting cadence.
TL;DR: the “plug-and-play” promise still benefits from a disciplined survey → logging → design → commissioning → verification workflow.
Risks and practical challenges to plan for
Balanced project planning means acknowledging where implementation can get stuck:
- Space constraints: MCC rooms and press-line cabinets may be full; adding hardware can trigger enclosure upgrades.
- Cable routing: connecting to braking resistors may require long runs that affect EMC and voltage transients if not designed correctly.
- OEM and insurer sign-off: machine OEMs may require approvals to maintain warranties or safety certifications; insurers may want evidence of compliance and workmanship.
- Downtime risk: even “hours” installs can slip if access is restricted or drawings don’t match as-built panels.
- Cybersecurity (if connected): if remote diagnostics or cloud reporting are used, confirm network segmentation, authentication, patching responsibility, and data ownership. Guidance such as the NIST Cybersecurity Framework can help structure expectations (even outside the U.S.).
TL;DR: the main risks are space, cabling/EMC, third-party sign-off, downtime management, and cybersecurity if connectivity is involved.
Commercial rollout and where it fits in industrial decarbonisation technologies
IR Power has indicated commercial deployments starting around 2026, targeting high-energy, cyclical applications first (notably press lines and heavy mixing/processing assets). This sequencing makes engineering sense: it is easier to demonstrate value where braking energy is frequent and measurable.
Within the broader landscape of industrial decarbonisation technologies, braking resistor energy recovery is best viewed as an electricity demand reduction measure. It does not replace electrification, heat recovery, or process redesign—but it can complement them by lowering kWh per unit output on specific assets.
TL;DR: reducERS is an asset-level electricity reduction retrofit that can support wider decarbonisation programs, particularly in high-cycling, high-inertia machinery.
Conclusion
Industrial regenerative braking is a mature concept, but many plants still dissipate braking energy as heat because retrofitting regeneration has historically been expensive or disruptive. reducERS appears aimed at reducing those adoption barriers through product standardisation and a pay-for-performance rental structure.
The engineering reality is that outcomes will vary: savings apply to specific machines, not entire sites, and depend on braking intensity, utilisation, baseline drive capabilities, and how recovered energy is buffered and reused. A credible project should include clear technical specifications, compliance documentation (CE/UKCA, EMC, safety considerations), and robust measurement and verification aligned to recognised protocols.
TL;DR: reducERS could be a practical VFD energy efficiency retrofit where braking is frequent and currently wasted—provided the technical integration, compliance, and M&V plan are solid.
FAQ
Q: What is industrial regenerative braking, and how is it different from braking resistors?
A: Industrial regenerative braking occurs when a motor generates electrical energy during deceleration and pushes it onto the drive’s DC bus (DC link). Braking resistors dissipate that energy as heat when it can’t be reused. Energy recovery systems aim to capture that energy and reuse it, reducing the electricity the asset draws from the grid.
Q: How is reducERS different from a traditional regenerative drive or an active front end?
A: A regenerative drive/active front end typically converts DC bus energy back to AC and exports it upstream to the plant’s electrical network, often with more extensive power-quality and integration considerations. reducERS is positioned as a braking-circuit retrofit that focuses on capturing energy otherwise dumped into resistors, emphasising standardised modular installation and a pay-for-performance business model rather than a full drive replacement.
Q: Does connecting to the braking circuit affect machine safety or compliance with existing safety integrity levels?
A: It can, which is why a safety and compliance review is essential. Braking performance, over-voltage protection, and drive safety functions (such as Safe Torque Off, STO) must remain correct under all fault conditions. Any retrofit should come with CE/UKCA documentation where applicable, EMC evidence, and an updated machine risk assessment; in some cases, functional safety standards (e.g., IEC 61508 / IEC 61800-5-2 depending on architecture) may be relevant.
Q: Can reducERS integrate with SCADA/EMS/BMS to show recovered energy and CO₂ savings?
A: Many industrial energy systems support integration via standard industrial communications (for example, Modbus TCP, OPC UA, PROFINET, or EtherNet/IP), but you need to confirm what reducERS provides. For credible reporting, the recovered/saved energy should be based on agreed metering points and a defined calculation method, ideally aligned with an M&V protocol such as IPMVP.
Q: What are the main constraints that reduce savings from braking energy recovery retrofits?
A: Savings are typically lower when braking events are infrequent, when the plant already uses regenerative drives or common DC bus sharing, or when there is limited opportunity to reuse/buffer energy at the moment it is generated. Power-quality constraints, space limitations in MCC rooms, and complex OEM approval processes can also affect feasibility and cost.
Q: Is reducERS available outside the UK, and can it be combined with energy-efficiency incentives?
A: Availability depends on IR Power’s deployment plans and local compliance requirements (e.g., CE in the EU, UKCA in Great Britain, and other regional certifications). In many regions, energy-efficiency retrofits can sometimes be combined with grants, tax incentives, or utility schemes, but eligibility is country- and program-specific—confirm with local agencies and ensure the project has robust metering and verification to support incentive claims.