Water Boost

Combustion engines will remain part of our urban mobility for quite some time to come, and play a not insubstantial and honest part in CO2 reduction. One way to meet the future requirements of Euro 6/2 or Euro 7 is also to continue optimising them.

Our key development area is the optimisation of exhaust emissions performance as well as performance development, both for petrol and diesel engines. Water injection (WI) can make a significant contribution in the future. Here, small amounts of injected water protect the engine against overheating. So-called “enrichment”, i.e. cooling by injecting additional fuel, is no longer required. At high engine speeds or torques, i.e. when demanding high engine power, the exhaust emissions are also reduced concurrently, directly in the engine. The water provides component protection, i.e. a cooling effect, and a significant amount of fuel is also saved (up to 30% at full load). The technology is mainly applicable to petrol engines. Investigations have demonstrated that this technology can also have a positive application in diesel engines.

With this technology, there are two key development objectives – emissions reduction and performance increase.

Therefore there is no conflict between these two topics at all. The core element of the water injection technology is the injection of a fine water mist in the induction path or in the charge air prior to ignition of the fuel or fuel-air mixture, providing effective cooling through the high evaporation enthalpy of the water. This only requires very small amounts of distilled water, which is carried in the vehicle in a small separate tank. If the water reservoir is used up, the engine continues to run without any problems – just without the power increase and with “normal” exhaust emissions.



The ISO 31120-1:2022 describes road vehicles Injection water (water boost) quality requirements.

This document specifies water quality used for water injection in internal combustion engines. This document defines quality requirements for injection water including instructions for storage, container materials and production. Testing procedures are also defined.

If you follow the link, you will find an overview. TESONA is not responsibility for the content.

TESONA has developed corresponding series-production technologies ready for application and qualification within mass-production automotive manufacturing.

Our key development areas for water injection in summary:

  • Design, detail design and specification of single components for WI systems
  • System detail design and integration
  • System heating (SHS heating, Smart Heating System)
  • Prototype construction
  • Test and validation
  • Material analysis
  • Filter analysis
  • Investigation of contamination to avoid algae formation when using demineralised water