The engineer who thinks technology, sustainability and economics together.
For developers, asset managers and project managers. From the first idea to ongoing operations. Direct and personal.
The Challenge
ESG strategy set, CRREM path calculated, measures assembled. But will the heat pump fit in the plant room? Are the shaft cross-sections adequate? Do the flow temperatures match the existing building? Tools deliver scenarios. Whether they work in the actual building is a question only someone can answer who understands both: calculation and building.
And as long as that question is open, you carry the risk.
Energy concept implemented, systems installed. But consumption exceeds projections, and tenants are complaining about draughts or overheating in summer. Heat recovery, control curves, hydraulics: the facility manager sees numbers and complaints, but not the causes. The problem rarely lies in the technology itself — it lies in the gap between planning and operation.
With every month, the need to explain yourself to your client and tenants grows.
New construction, revitalisation, campus development. Architects design, consultants size, everyone optimises their own trade. But who ensures the energy and sustainability concept holds across all trades? Who checks whether the sum of individual solutions adds up to a functioning whole?
In the end, you are responsible for the result. Not the consultants.
See the whole picture. Get to the point. Solutions that work. Not just on paper.
About me
I am Johannes Bracke, M.Sc., mechanical and energy systems engineer. I learned how buildings come together in MEP planning, and over more than twelve years at Baumann Consulting and Drees & Sommer I worked on projects that left little room for error: data centres, office buildings, industrial buildings and campus developments in Germany, Switzerland and the USA.
When you work with me, you work directly with me. No junior processing your documents. No project manager between you and the expert. You get a sparring partner at eye level who speaks your language, understands your goals, and honestly tells you where the biggest levers are.
Independent of manufacturers, software vendors and internal hierarchies. What I recommend, I recommend because it is the right solution for your building.
In complex projects I work closely with architects and general planners. On buildings where architecture, technology and sustainability only work together. I lead these projects in German and in English, with international clients, investors and planning teams.
I know the perspective of the developer, the planner and the operator. And I know where they diverge.
12+ years experience · M.Sc. Energy Engineering · Projects in D, CH, USA
How I work
I start with a prepared conversation: your project, your goals, your open questions. At the end there is a clear picture of where I can help and whether we are a good fit. Only then do we move forward.
I don't just check numbers — I check the reality behind them. For existing buildings that means: systems on site, operational data, scenario simulations. For new builds that means: concepts, sizing, the interplay of trades. As far as necessary. In the end I know where the real levers are and what pays off.
At the end you know what needs to be done. Which measure has the biggest impact, what it costs, and what it delivers. No reports for the drawer — a basis you can translate into decisions. If desired, I can also support you through implementation.
Initial Consultation
Every collaboration begins with a conversation. Free and non-binding. Either in person in the Rhine-Main region, by video or by phone.
An honest conversation about your project, your goals and your open questions. You get a clear picture of where I can help. I get a clear picture of what your project needs. No charge.
Now we get into the actual project. In a joint working session I listen, ask the right questions and work out with you and your project team exactly where you need support. After that I know your project well enough to give you a solid proposal.
If the first session has convinced you, we move into the actual work. As a sparring partner in the project, for targeted expertise or strategic consulting.
How I can specifically help
Every project is different. That is why I do not work with rigid service packages, but adapt my involvement to your situation. What all formats have in common: you get my full attention and experience, directly and personally.
You are looking for an experienced engineer who technically accompanies your planning team, ensures quality and provides the right impulses. I work as your technical consultant at eye level: I review concepts, question sizing, coordinate at the interfaces between trades and ensure the overall solution works. From the early concept phase through execution to operation.
You need a second opinion, a plausibility check or a targeted analysis. I come into your project for a clearly defined task and deliver a robust result.
You face a fundamental decision. Which energy concept? Which measures are truly worthwhile? Renovate or new build? I develop the decision basis with you so that you can invest with confidence.
Technical expertise in detail
The following areas of expertise can each be part of a project individually or in combination. Depending on what your project needs.
For new build and existing stock: energy supply concepts that bring together economic viability, sustainability and feasibility. From single buildings to campuses. Scenario comparisons with robust figures, integration of heat pumps, photovoltaics, storage and waste heat utilisation.
CO2 accounting across the entire building lifecycle: operational emissions and embodied carbon. Decarbonisation pathways that have been verified against the real building, not just on paper. Including circular approaches and assessment of material concepts.
Technical assessment at the real building rather than general benchmarks: CRREM analysis, stranding risks, EU Taxonomy compliance. What does the building need to stay on the pathway, and what does that cost? Decision bases for asset managers and investors.
KfW, BAFA, BEG and state funding programmes. Identification of suitable grants, technical evidence, application support. I calculate what actually remains after funding and assess when grants make a project viable and when they do not.
Dynamic simulation of thermal building behaviour across the full annual cycle. This enables precise sizing of building systems, early identification of comfort risks and validation of energy concepts before construction. Tools: IDA ICE, IES VE, EnergyPlus.
Flow simulations for complex room geometries, data centres and special applications. From cold-aisle/hot-aisle design to draught analysis in atria. Tool: ANSYS Fluent.
Dynamic daylight simulation for visual comfort, glare-free environments and energy savings through natural lighting. Relevant for highly glazed spaces, atria and deep building footprints. Methodology per DIN V 18599, radiance-based tools.
Thermal comfort per DIN EN 16798 and ISO 7730, summer heat protection, air quality. Answers to the question: do people feel comfortable in the building? Particularly relevant for atria, production halls and complex office environments where standard calculations reach their limits.
A second opinion for complex projects. I review concepts and sizing, question assumptions and support the planning team at the critical interfaces. On a level with the MEP planner, not as a control authority, but as an additional quality layer. Particularly valuable in the early planning phase, where the key decisions are made.
The decisive step between planning and operation: I verify that systems function as designed. From design review through functional testing to performance measurement. Per ASHRAE Guideline and LEED requirements. Without commissioning, simulation rarely becomes reality.
Buildings often consume 30 to 50 percent more energy than calculated. I identify the causes through systematic analysis of operational data, BMS evaluations, control curves and on-site inspections. Retro-commissioning where required. Result: a building that achieves the promised figures, not just on paper.
References
Publicly documented. At Drees & Sommer and Baumann Consulting.
| Type | Project | Services | Employer |
|---|---|---|---|
| Data Centre | Digital Realty, Frankfurt (FRA18–22, FRA27) | CFD simulation and energy supply concept | Drees & Sommer |
| Airport | Fraport Terminal 3, Frankfurt | Indoor climate concept and simulation | Drees & Sommer |
| Office Building | Dock 3.0, Frankfurt | Commissioning and building simulation | Baumann Consulting |
| Existing Building | Sparkasse Aschaffenburg | Energy retrofit and operational optimisation | Drees & Sommer |
| Life Science Campus | MedImmune Campus (AstraZeneca), USA | Retro-commissioning (120,000 m²) | Baumann Consulting |
| Mobility | E-Mobility Hub Wiesbaden | Charging infrastructure concept | Drees & Sommer |
New build and existing stock. In Germany, Switzerland and the USA. For developers, asset managers and project developers.
Specialisation
Data centres are among the most technically demanding building types. With the AI boom, energy demand is growing exponentially, while the Energy Efficiency Act tightens requirements: strict PUE limits, renewable energy quotas, waste heat utilisation. Those who plan today must plan for this future.
Sustainability in data centres is more than PUE optimisation. The biggest levers lie in site selection, energy supply, waste heat utilisation and circular construction and operating concepts. I bring experience from projects with colocation and hyperscale operators. German building regulations and American construction culture are not a contradiction for me — they are two tools towards the same solution. My focus: sustainability that pays off.
Why now
In the planning phase you correct with a few lines. On the construction site the same correction costs ten times as much. With current construction costs you have no budget for mistakes.
Many investments in energy retrofit do not achieve the promised savings. Tools generate packages of measures, but nobody checks whether they actually work in the real building. Misinvestments only become visible during operation, when corrections are expensive.
The right decision at the start is the cheapest one. But it needs someone who sees the whole picture. Not just the numbers in the tool.
The result
Instead of a strategy that looks good on paper: a concept that has been tested against the real building. You invest in measures that work, not in reports for the drawer.
Instead of unexplained excess consumption and subsequent discussions: a building that reaches its projected figures. Your numbers add up, and you can prove it.
Instead of silo thinking and open interfaces: a project in which all trades interlock. Someone sees the whole picture. Not somewhere in between. But by your side.
Contact
The best conversation is the one you have directly. Schedule an appointment or call. I deliberately work with few projects at a time so that each one gets my full attention.