Arne "Pump-Arne" Jonsson is the man behind the ECT system. He has been working as an international consultant for aerospace and pump companies for many years. His designs have been proven in field with efficency and long lasting life cycles.
He is an expert in energy systems and mechanical calculation. An engineer with a driving force to always optimize his solutions. From energy to design of impellers and turbines and production. "All large as well as tiny parts have to be optimized to have a reliable system. And since we have few components we can keep the cost down."
In beginning of 2000 Arne took the first steps in how to solve the problem with poor efficiency in the ORC (Organic Rankine Cycle) process due to the small temperature differance when using waste heat as source. The solution, the ECT Process, has astonishing doubled output compared to a standard ORC system.
"In our solution we can convert more of the available heat into mechanical work than what´s possible to do in the standard ORC process. That´s why we can get so much more".
To be able to optimize the complete system and electrical output you first need to understand the heat source. This is best done with a so-called temperature profile. It´s a graph showing temperature (Y-axis) and heat transfer (X-axis).
The Temperature Profile
To the left a Temperature Profile for waste heat is displayed. Here for a mid size diesel engine for a ship.
In this example heat goes from 330 to 50 degrees centigrade. And the heat transfer up to 40 MW.
Source: Maria Jonsson, Advanced Power Cycles with Mixtures as the Working Fluid, Dr Thesis, KTH 2003. Graphics©: ECT Power AB.
The standard ORC process
Once you have the temperature profile you can start the design of the internal ORC circuit. (Organic Rankine Cycle).
In a normal ORC process heat exchanges are used for pre-heating, evaporation and super heating of the fluid. This generates steam for the turbine. When the fluid leaves the turbine it is cooled in a condenser (also a heat exchanger).
The ECT ORC process
One important part of our invention is a highly improved heat transfer process (pat.pend.).
As you can see in the diagram the "used" area under the heat source is much larger=more heat transferred compared the the standard process above. This is a key to the increased electrical output.
We achieve this by have an adepted evaporation. Not at a constant temperature.
The heat transfer process in combination with own designed high performance turbine (ŋ around 90%) and pump gives the high output (also pat.pend.)