'efficiency improving' is correct and can be used in written English.
It is often used as an adjective phrase to describe something that is actively working to increase efficiency. Example: The new technology implemented by the company is aimed at efficiency improving measures, such as automating processes and reducing human error.
This has resulted in quadrupling efficiency, improving our productivity and delivering bottom-line impacting results to our customers.
Because a C.V.T. more closely matches the engine's output to the vehicle's speed, the engine should always be operating at optimum efficiency, improving fuel economy.
Biometrics has helped to promote development in certain cases, particularly with regards to increasing efficiency, improving service delivery and accountability, and allowing poorer countries to build sophisticated identification systems in a relatively short period of time.
PWC said its research showed that UK companies were planning to spend the next year cutting costs, improving efficiency, improving service to existing customers and concentrating on the domestic market.
Plant genetic engineers are working to improve specific economically important plant varieties by increasing their photosynthetic efficiency, improving their nutritional quality, and transferring to them such favourable properties as the ability to fix atmospheric nitrogen, as do legumes, and to better resist diseases and tolerate herbicides and natural environmental stress.
Some efficiency improving design options were considered and the resulting increases in manufacturing cost and retail price were estimated.
Energy consumption is again low, with an improvement of 41.7% and energy efficiency improves 128.1%.
And, as LED energy efficiency improves, he thinks consumers will upgrade their LED fixtures with lower watt versions.
Religious freedom was established, government efficiency improved, and the Napoleonic legal code has served continental Europeans well for two centuries.
There's also an animation of vines that grow representational leaves as the driver's efficiency improves.
He did not sustain any more concussions, and his tackling efficiency improved.
