The next generation Organic Rankine Cycles

IWT Strategic Basic Research (SBO)

Today’s process industry (cement, glass, paper, plastic, chemical, ...) disposes over an enormous amount of waste heat. Experts assume that the annual unused industrial waste heat potential amounts to 140TWh in Europe alone, implying a CO2 reduction potential of about 14M ton of CO2 per annum. This waste heat is typically available at a lower temperature and can be recovered in the form of electrical power with Organic Rankine Cycles (ORC) technology. Hence, ORC technology has a big economical potential and helps to realize the EU ’20-20-20’ goals.

Several companies offer ORC for waste heat recovery. Notwithstanding the substantial existing interest  in this type of technology, there is still a big amount of waste heat in industry for which ORCs could be used. Studies show that investments in these cycles are often not favorable if the payback time or the internal rate of return is considered.

Two main technical reasons can be identified:

Firstly the efficiencies of the cycles are too low for low temperature waste heat sources, resulting in too low energy production. Secondly, the current ORC’s on the market aim at a too high waste energy flow.
First research will focus on new cycle architectures raising efficiency. One promising step is going towards supercritical cycles, using supercritical fluids. These fluids are already used in cooling systems. The progress will be realized through thermodynamic modelling and experimental validation. An improvement of about a factor of 20-25%, which is similar to steam cycle improvements, is expected.

Secondly the goal is to investigate efficient systems for smaller power ranges, aiming at creating the potential for a lot of small scale systems on the market. Therefore, a specific technology has to be developed, by means of advanced CFD algorithms. This development will be made in close cooperation with an industrial research partner.

Two other important factors are also influencing the potential application of these systems:

First it is of great importance to develop smart control algorithms which can take care of a varying load. The project results will open again more possibilities for these cycles as a lot of heat sources have a strong variable character.

Secondly, both financial and economic constraints and opportunities should be clearly understood. In previous studies the combined effort of economists and engineers has proven to give fruitful research results. Therefore the whole project will not only be benchmarked to technical possibilities but also to financial and economic benefits.


Further information

This project is supported by IWT Strategic Basic Research (SBO) for the period January 2012 – December 2015.

More information on ORCNext is available on the project website: