Low temperature heat with 100 to 150 C (212 to 302 F) occurs in many places, as industrial waste heat, as waste steam emission, as thermal energy from solar collectors, heat from biomass plants, in geothermal power etc. The video shows waste steam emissions from a paper factory. If we estimate that there are about 300 litres of steam blown off per second, then this amounts to 677 kW of thermal energy. Our technology could generate about 60 kW of electricity from this currently unused resource. The problem with heat at lower temperatures is, that it is difficult to use with current technologies. That’s why we are developing the “Condensing Engine”
Now, what actually IS a condensing engine? Well, it is a steam engine, only it uses the condensation of steam and the arising vacuum as the driving force, not the pressure of the steam. It runs at a temperature of 100°C (212 Fahrenheit), and under atmospheric pressure. Its original form was invented by James Watt in 1772; we have now improved the energy conversion cycle and the efficiency quite dramatically, making this again an interesting technology for energy recovery from waste heat, and renewable energy conversion.
Why do we develop such a thing: there’s an enormous amount of unused heat (or better: thermal energy) with temperatures of 100 to 150°C (212 to 300 Fahrenheit) around, e.g. the waste steam which is blown off by industry, solar thermal energy from flat plate collectors (much cheaper than concentrated solar power), geothermal energy etc. The Condensing Engine could use this energy to generate electricity.At Southampton University, we are currently working on research into, and the development of such an engine, have a look a our facebook page.
What’s so interesting about it? it is a simple machine, and has a number of compelling advantages:
- It uses water as working fluid. Water is non-corrosive, not toxic, cheap, readily available and not inflammable. These are big advantages compared with the fluids used e.g. in the “Organic Rankine Cycle” systems.
- It works at atmospheric or lower pressures, and boiler explosions are not possible (google “boiler explosion”, look at the images and you will find why this is important..). In consequence, these machines can be operated everywhere and safety, inspection and maintenance effort and costs are low.
- It is a very simple machine, implying cost-effectiveness.
And, what is this web site all about then?
A number of things.
- Firstly, we want to create a web page for the condensing engine as an information platform about a technology which was to all practical purposes forgotten, but which has been re-discovered, improved and which could contribute to energy efficiency and energy generation with renewable sources.
- Secondly, we want to provide information which is otherwise difficult to obtain
- Thirdly, we are planning a crowd funding project to finance the design, construction and testing of the first prototype engine. In order to maximise its effect, we need to inform people.`