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During spring 2024 a candidate group with Simon, Erik and Richard will use the Linköping University GREC Lab-Model v.3 for experiments.

The Green Revolution Energy Converter (GREC) sustainable research at Linköping University will put their own physical GREC LabModel v3 to work. This unique project aims to answer if a "real world" revolving physical "Work Generating Volume" will behave as predicted in earlier Li.U theoretical research. Does theory and reality converge? Is the GREC a future crucial climate-positive concept for an adjustable clean energy generation?
Linköping University are world leaders in GREC technology and this group is on the cutting edge.


The severe impacts of green house gas emissions on the global warming is today a fact. The emissions can be coupled to several different sectors where heat and electricity production were the sectors with the highest increase of CO2 emissions in 2021. In Economics and Politics the word ENERGY is often reduced to something to sell, distribute, consume and tax. Our industrial society is built on that. In natural sciences energy is larger than that, energy is a property that is not created nor destroyed, although energy can change in detectable form. This change in form is what the Green Revolution Energy Converter is all about, to convert heat energy into kinetic energy in a totally new machine - The Green Revolution Energy Converter - GREC The GREC converts heat energy to kinetic energy by pressure-volume work. The kinetic energy may be used "as is", or to generate electricity by connecting a generator to store and/or distribute its power. Simon, Erik and Richard are investigating this new technology aiming to be applied both in the electricity production sector and the transport sector.

The GREC sustainability part at Linköping University Sweden

From the left: Simon Eriksson, Erik Widström and Richard Zetterman with the Li.U LabModel v.3

The Project's Starting Point

A leaking LabModel v3 that needs to be prepared and sealed in order to measure pressure variations from a revolving Work Generating Volume (WGV) at different speeds between heat reservoirs of different temperatures.

First Part Project Goal

Obtaining a tight enough LabModel v3 with a motorised revolving WGV.

Overall Project Goal

To be able to revolve its WGV with electric control at different speeds while logging pressure and average temperatures.
The goal is to retrive logged data in a repeateable form and present it with reliable extrapolations for much larger volumes.

What distinguishes a GREC LabModel from a GREC Prototype?

A GREC PROTOTYPE should generate a power surplus and be built for a specific temperature gradient condition. We would base our calculations on a WGV of 25 to 250 litres of gas or a vapor close to its condensation point. Maybe running in an environement where you only need an electric switch for the motor that revolvs the WGV.
In order to construct a prototype made to deliver a certain power requirement in a particular environment, one must be clear about the limitations of the concept and test its properties with the variables of the environment. That's why we need a working LabModel.

A GREC LAB MODEL is a small gadget with a lot of electronics. With a tiny WGV of only 25 cc the LabModel is really under-dimensioned but it allows us to study the limits of phenomena with experiments that will help us interpret what is going on, and which are the dominant factors and their limits, in order to be able to calculate, construct and set dimension with the support of established knowledge in thermodynamics, fluid dynamics, heat transfer and other sciences.

The Green Revolution Energy Converter – GREC – converts HEAT energy to KINETIC energy.

The GREC converts heat energy to kinetic energy by pressure-volume work. The kinetic energy may be used "as is" or generate electricity by connecting a generator.

The GREC Technology

In thermodynamic terms the GREC is a closed system with a moving boundary where the GREC converts heat energy to kinetic energy. The GREC heats up and cools down its internal large sliced WGV efficiently, fast and repetitively, resulting in internal pressure changes.
These internal pressure changes are used by its moving boundary to generate kinetic energy. You may think of the GREC as a revolving Carnot heat engine controlled by computer logics. Please find the theoretical presentation of the GREC on this link:
GREC Theory Presentation

The GREC is a new technological solution to tackle climate change and technologists at Linköping University are pushing the challenge of a transition to fossil free energy systems. Their theoretical research, construction and building, and following experiments of the GREC Lab Model v.3 are very important steps in a climate positive project that will feed several successful research projects over time...
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Contact information at nilsinside AB
Nils Karlberg, tel +33 608 53 15 93, theory & technical questions
Sophia Karlberg , strategy & admin questions

The GREC Project