About
About Mexel Energy Sustain.
Mexel Energy Sustain (Pty) Ltd is a South African company focused on cooling-water and thermal efficiency. We combine Mexel chemistry with IoT dosing, data and verification to help large energy and industrial users reduce cold-end losses in a disciplined, engineering-led way.
Our work sits at the intersection of energy efficiency, water treatment and system performance. TES is our practical framework for applying this at wet-cooled coal units and industrial cooling-water systems.
Our technical approach
We do not start with a catalogue of products. We start with how energy and water are being used at the cold end: condensers, cooling towers, exchangers and critical cooling-water loops. From there we design an intervention that makes technical sense for that specific system.
TES is the way we structure this thinking: Mexel®432 chemistry, IoT dosing, a focused cooling-water performance view and a clear verification framework. Each element is simple; the value is in how they work together.
Principles
- • Transparent, data-driven, engineering-first.
- • Respect existing station and plant protocols.
- • Scope tightly; avoid overpromising or overselling.
- • Let measured results, not claims, drive decisions.
Why TES exists
At many wet-cooled stations and industrial sites, the cold end quietly erodes performance. Biofouling, scaling, corrosion and ash or mud deposits reduce condenser cleanliness, increase cooling-water temperatures and make TR / TTD unstable. Multiple chemicals are dosed, but their true impact on energy efficiency is often unclear.
TES exists to make this part of the system visible and manageable. By focusing on cooling-water and condenser performance, we help clients recover efficiency that is already sitting in their assets, without claiming to replace proper operations, maintenance or long-term capital projects.
Our work with Eskom and large energy users
Mexel®432 has been through rigorous independent technical evaluation, including application at Kriel and a formal testing protocol for Tutuka. We understand the realities of working on live stations: water-quality constraints, operational risk, safety, and the need to align with engineering, chemical services and station management.
Our goal is straightforward: help stations stabilise condenser performance, not replace maintenance or plant disciplines. TES is structured so that station teams, engineering and independent referees can see the same data and draw their own technical conclusions.
Evidence and verification timeline
TES is built on documented work with ASME PTC 12.2 standards, independent referees and structured verification. Key milestones:
Kriel Power Station
Initial Mexel®432 application
First Eskom site where Mexel®432 was applied in cooling-water service. Station data indicated improved condenser performance during treatment period.
Verification Standard
ASME PTC 12.2 Aligned
Performance gains are validated using ASME PTC 12.2 methodology, defining baseline → intervention → post-intervention steps for rigorous TES verification.
Independent Referee
Water Research Commission
The WRC can act as an independent referee for TES pilots, reviewing methodology and results under their established frameworks for water-treatment research.
IoT Infrastructure
Thingy:91X dosing skids
TES dosing skids based on Nordic's Thingy:91X platform installed at Tutuka, providing traceable dosing records linked to condenser performance data.
Carbon Credit Development
Emissions reduction monetization
Working with Brundtland Consulting, we develop VCS-compliant carbon credit methodologies from verified efficiency improvements.
ASME PTC 12.2 verification provides the audit-grade documentation required for carbon credit registration under international standards (VCS) and South African frameworks (DFFE).
Efficiency gains → Measurable emissions reduction → Carbon credit revenue
Strategic Engagement
JET & transition context
TES is positioned within the Just Energy Transition context as a practical efficiency intervention that can extend asset life and reduce emissions intensity.
Documentation including the TES Master Evidence Pack and engineering protocol is available for qualified enquiries.
Industrial cooling-water clients
Beyond power stations, many industrial sites depend on reliable cooling-water systems: mines, refineries, steel plants, and large processing facilities. They face the same underlying issues – biofilm, corrosion, scaling, solids – often with variable raw-water quality.
TES principles translate directly into these environments. We adapt the same Mexel®432 chemistry, dosing and data approach to the specific cooling loops and constraints of each plant, with the same emphasis on transparency and measurable results.
Talk to us about your cooling-water or TES questions.
If you are responsible for a wet-cooled unit or a critical industrial cooling-water system, we are happy to explore whether TES and Mexel®432 are a good fit. A short, technical discussion is usually enough to see if there is a realistic path.