BLuEngineering

Results that add up.

All projects have been anonymised for data protection reasons. The figures are real.

Our references

Projects from practice – across different sectors, with measurable results.

We show what building services engineering with an economic focus achieves: in municipal properties, existing residential buildings, commercial real estate and industry. Every project meets the same standard: design that proves itself in operation.

Existing multi-storey residential building

Case Study 01

Apartment Building

Apartment building, 24 residential units, built in 1974, housing company, Bavaria

Residential

Services

  • ·Energy cost analysis
  • ·Heating replacement
  • ·Funding application handling

Starting point

The oil heating system, installed in 1997, was close to failing. The building’s energy consumption was around 35% above the benchmark for comparable properties, yet it was unclear which measure would have the greatest impact. The housing company faced a fundamental decision: simply replace the system or optimise it systematically? Requirements under the German Buildings Energy Act (GEG) and ESG reporting obligations added to the pressure to act.

Challenge

The building had no hydraulic balancing and poorly insulated distribution pipes. Because of the high flow temperatures, a heat pump could not be shown to be economically viable without an analysis of the existing system. The owner needed a basis for decisions that brought together system choice, cost-effectiveness and funding strategy – not three separate expert reports.

What BLuEngineering did

  • ·Complete energy cost analysis: consumption data, load profiles, existing plant, heating curve evaluation
  • ·Heat load calculation to DIN EN 12831
  • ·Comparison of options: gas condensing boiler, hybrid system (heat pump + gas), brine-to-water heat pump
  • ·Cost-effectiveness calculation including funding for each option
  • ·Decision: hybrid system with air-to-water heat pump + gas condensing boiler to cover peak loads
  • ·Funding-optimised engineering design, BEG EM application (federal funding for individual measures), tendering and contract award management
  • ·Site supervision, support with hydraulic balancing + commissioning
  • ·Operational optimisation in the first year of operation

Results

31%
lower heating costs – every year, permanently
100%
of BEG EM funding applied for and paid out in full
5.8 yrs
payback period including funding

What made the difference

The decision in favour of the hybrid system rather than a heat pump alone only emerged from the heat load calculation: the flow temperatures were too high for economically viable heat-pump-only operation. Without this analysis, the system choice would have been either wrong or more expensive.

Office and administration building with a glass façade

Case Study 02

Office Building

Office and administration building, 3,800 m² net floor area, built in 1989, private owner, southern Germany

Commercial / Administration

Services

  • ·Building services design
  • ·Energy concept
  • ·Funding application handling

Starting point

The owner was planning a comprehensive modernisation of the building to reduce vacancies and cut rising energy costs. The existing gas heating and the outdated ventilation system without heat recovery were causing high operating costs. At the same time, the building was to become more attractive to tenants – with low service charges as a selling point. GEG § 71a was relevant: the installed heating capacity exceeded 290 kWth.

Challenge

The building was let and had to remain partly in operation during the renovation. The technical complexity was high: heating, ventilation and cooling had to be renewed in a coordinated way, without individual trades ignoring interdependencies. The owner had not previously used funding programmes for non-residential buildings (BEG NWG) – the requirements were unknown.

What BLuEngineering did

  • ·Energy concept: simulation of energy flows, comparison of supply concept options
  • ·Decision: brine-to-water heat pump for base load, gas condensing boiler for peak load, central ventilation system with high-efficiency heat recovery
  • ·Building services design for service phases 1–9 (HOAI, the German fee structure for architects and engineers): heating, ventilation and cooling coordinated from a single source
  • ·GEG § 71a: technical commissioning management (TIBM) integrated as a mandatory service
  • ·BEG NWG application: systemic renovation of a non-residential building
  • ·Construction phase management during ongoing operation: section-by-section implementation coordinated with the operator
  • ·Commissioning monitoring

Results

44%
lower energy costs compared with the previous year
62%
CO₂ reduction compared with the old system
6.3 yrs
payback period including BEG NWG funding
2
new leases – with low service charges as a selling point

What made the difference

Coordinated building services design ensured that ventilation and heating were planned as an integrated whole. The owner had been unaware of the BEG NWG funding application until then; this alone significantly improved the investment calculation. During trial operation, commissioning monitoring identified incorrect parameter settings in the heat pump control that would otherwise have caused hidden additional costs for years.

Existing hotel building

Case Study 03

Three-Star Hotel

Three-star hotel, 68 rooms, 4,600 m² net floor area, built in 1982, family business, Bavaria

Hotels / Hospitality

Services

  • ·Energy cost analysis
  • ·Heating replacement
  • ·Hot water optimisation
  • ·Funding application handling

Starting point

Energy was the business’s second-largest cost item – after staff. The gas heating system from 2001 was still running, but inefficiently. Hot water consumption for rooms, kitchen and laundry was high and difficult to measure. The operator had neither consolidated consumption records nor any idea of how much each system was costing.

Challenge

Hotels have particularly high and at the same time fluctuating loads: hot water demand around the clock, ventilation requirements in the kitchen and rooms, cooling during summer peaks. The system had to be renewed while the hotel remained open – with minimal disruption for guests. At the same time, the budget was tight: every investment had to pay off clearly and demonstrably.

What BLuEngineering did

  • ·Complete energy cost analysis: gas consumption, electricity, hot water – broken down by usage zone (rooms, kitchen, laundry, general)
  • ·Identification of the biggest cost drivers: hot water generation (42% of heating costs) and outdated control technology
  • ·Comparison of heat supply options: gas condensing boiler, heat pump + buffer tank, hybrid solution
  • ·Decision: air-to-water heat pump with a large-volume buffer tank for the hot water base load, gas for peak load
  • ·Optimisation of hot water circulation: new controls reduce circulation losses
  • ·Funding-compliant engineering design, BEG EM application, tendering in construction phases during low-occupancy periods
  • ·Commissioning monitoring: monitoring of the complex commissioning process with a focus on the share of hot water covered by the heat pump

Results

38%
lower energy costs – with the same level of operation
71%
of hot water demand covered by the heat pump
5.1 yrs
payback period including BEG EM funding

What made the difference

The energy cost analysis showed that almost half of the heating costs were attributable to hot water – not space heating. Without this analysis, the investment would have gone into space heating and the real cost driver would have remained untouched. Construction phase planning ensured that no room was without hot water for more than one night. In the third month, commissioning monitoring found and corrected a seasonal control deviation in the heat pump – raising the share of hot water it covers from 58% to 71%.

Your project is different – that’s normal.

Every building has its own starting point. Get in touch – we will show you what is possible in your specific case.

Enquire about your project