History: Infinity Turbine was started in 2008, but its roots go back further into the 1980’s when I was buying and selling legacy steam engines into the forest products.
Scope: Infinity has experimented with just about every type of expander, focussing on those below 500 kW in output size, and more on the smaller end of the spectrum (less cost to experiment and develop).
What We’ve Learned: If your expander has more than one moving part, it will break. This is a lesson learned, and capitalized on by Capstone Turbine. Beyond that, even having one moving part, will break. That is why we have ultimately focussed on tribo-effect, and a solid-state turbine using phase change Rankine technology. Another technology (with low efficiency) is the TEC Thermo Electric Coolers or Thermoelectric Device, or Peltier effect, which can produce electricity from heat.
Market: We have on focussed on low-grade heat (at or below 100C), and the small commercial market. While the residential market it huge, entrants into that market have failed quickly (huge support needed, and lack of payback with existing low priced competing grid based power).
Working Fluid: Our original development was with Honeywell Genetron R245fa and R134a. The costs of those proprietary refrigerants is expensive, and will soon be rendered unmarketable in most countries with active CFC programs. We have looked at, and are focussing on liquid CO2, and supercritical CO2 (30 C or 89 F).
Business Model: Our current business model is to sell plans we have already developed and documented (blueprints). We have build a large number of expanders, and put some into systems (IT10, IT50, and IT250). Our specialty is in the small end of prime movers, and to that end, we are focussing on selling plans for rotating turbomachinery, and developing a solid state turbine. One of our new products is a APU for drones, using a air-breather gas turbine, but then evolving into a electrostatic turbine.
3D Additive Printing: We have come to the conclusion that a 3D metal (or ceramic) printed turbine generator, with one moving part, may be able to provide a cost effective solution when mass produced. When parts are produced larger than a few inches, distortions from final heat processing (sintering) will occur and necessitate machining to bring into tolerance. The other option is to produce smaller parts, then have a heat coating to protect the base material.
Residential Market: There are significant challenges, which include:
– ORC is a waste heat energy solution, and if you have to pay for the fuel, or to harvest it, it does not have a payback (i.e. solar energy)
– ORC is designed for 24/7 heat supply. Any fractional time heat supply sources have no payback
– Most residential waste heat sources are time limited (i.e. hot water heaters only operate a small amount of time, solar energy is only part of the day, etc.)
– Most residential applications for CHP have no payback, and required significant amounts of support. All result in no profit to the equipment supplier. A good example is the recent attempt of the residential sterling engine by Dean Kaman.
Waste Heat: Generally, any heat source that can be converted to a liquid (water, glycol, oil, etc.) and is free, is a good source for a ORC system. If you have to pay to harvest the heat (like solar), then it does not make economic sense, unless your grid based power is very expensive.
ORC and Phase Change Dynamics: A big part of the equation for a waste-heat-to-energy recovery operation is the necessity for cooling flow, to condense the gas to a liquid. This is often overlooked by developers, and can be a big power draw, rendering a installation commerically infeasible (i.e. no payback).
Commercial ORC Builds: For all models of the turbine with induction AC generator, you will need a grid-tie interconnection device. The grid-tie integrates the AC Induction motor/generator into the grid, whether it be a local (in-house) or public grid connection.
What Plans Are Offered ?
– turbine/expander with generator
– consulting is additional
ORC and Supercritical CO2 Performance Charts – Buy Via PayPal $100
USD: Note – when purchase is complete, download will automatically
begin to your computer.
When purchase is complete, Click on RETURN TO INFINITY TURBINE LLC and
your download will begin. Otherwise, we will email you a download link or the pdf publication.
Heat Rate and Efficiency: If you have to pay for your heat or fuel, the ORC process does
not make any financial sense to install. ORC is a bottoming cycle, and designed for waste heat (free heat). As for supercritical CO2 Brayton Cycle, it is about the same or lower efficiency as ORC at or below 200 C. Above 500 C The S CO2 cycle will start to have
efficiencies from 40+ percent. This process needs large amounts of funding to be fully
R245fa: Our standard developed turbine generator system uses R 245fa (Honeywell Genetron) system which operates between 80-110 C within our parameters. This represents 4-8 percent efficiency. R245fa has proven to be the most efficient refrigerant in this heat range.
Condenser: The standard systems use a water cooled condenser. Expect a temperature increase of 5-10 C from the input and exit water flow. There are a few novel condenser designs which will allow a greater cooling rate, and lower water flow rate. These include ejector cooling, Zeolite pellet condenser design, and using our new counterflow turbopump, which uses the turbine power to spin a turbopump that cools the exiting gas from the turbine as a pre-heater. There are also nano-fluid additives which may increase heat transfer efficiency in working fluids.
Organic Rankine Cycle ORC Simplified:
(a) Your heat is provided in the form of thermal liquid (water, glycol
or oil). If you already have heat exchanger equipment, then you can
just use water, glycol, or a better alternative is thermal oil. If
you don’t have a heat exchanger to capture your waste heat, then we
recommend a hot air to thermal oil exchanger (they are available
everywhere). The source of the heat can be geothermal, engine waste
heat, gas turbine heat, solar collector, industrial waste heat, steam,
etc. Your heat source in the form of a liquid then goes through the
evaporator heat exchanger. This is where the working fluid for the
ORC turbine gets vaporized and pressurized. The heat source should be
at least 80 deg C. Once it passes through the evaporator, it comes
out at about 10-15 deg C cooler. This can then be used for additional
process heat (CHP hot water or chiller).
(b) The working fluid for the ORC closed system is pressurized by the
evaporator, then is expanded by our turbogenerator. This produces the
shaft horsepower to turn the generator and produce electricity. Of
course, you can have the turbine power a generator, pump, or whatever
(c) The expanded working fluid then goes through a condenser to
return the vapor to a liquid state. The condenser requires some
method of cooling fluid, typically water which is provided from a
cooling tower, or ground based geothermal (the ground has a constant
temperature of 15 deg C or less temperature). The liquid is then
pumped back into the evaporator unit to complete the cycle. Only
environmentally friendly working fluid is used in the system.
So, the basic system has a evaporator, turbogenerator unit and
condenser. The temperature difference between the evaporator and
condenser heat and cooling flows must be at least 125 deg F, or about
65 deg C (difference).
Our specialty is distributed energy and developing power systems for
business that have unique power opportunities by utilizing waste heat.