This is way too cool to overlook. Atsushi Takano at Nikkei Monozukuri magazine reported in Tech-On that IHI Corp of Japan has developed a compact gas turbine generator unit. The gas turbine and generator set is so small it fits in a suitcase.
All by itself, running on propane the unit autonomously generates electricity. IHI is saying this is the first time in the world that a portable gas turbine generator has been used to autonomously generate electricity. So be it. It’s also incredibly small.
The IHI gas turbine generator used for the unit is approximately 80mm (3.15”) in diameter and 120mm (4.75”) in length. It starts up and stops by using push button switches. Rated power generation gets going about 30 seconds after the starting operation. It comes to a complete stop about two minutes and 30 seconds after the shutdown signal is sent. There must be a top quality bearing set inside.
There is one sign of the unit’s efficiency; the exhaust gas temperature is 70°C or 158ºF. While that would scald skin, its hundreds of degrees lower than a first thought would suggest. That low temperature implies the unit is exceptionally efficient at combustion energy conversion to rotating mass.
Propane, or LPG isn’t the only fuel the unit can handle. The company confirmed to Tech-On that the gas turbine generator unit supports a variety of fuels such as kerosene and light oil.
IHI has been at this sort of thing awhile. Some readers might realize that IHI is a world significant turbocharger manufacturer with serious skills. The company also has aerospace experience with Japan’s space program. The engineering skill set seems to be very proficient at the micro level. The company has used the skills in the research and development of the portable gas turbine generators based on its experience in ultrahigh-speed rotating machinery technology developed for its jet engine and turbocharger businesses. It looks like a natural follow on business.
The Tech-On writer notes that IHI suggests that by taking advantage of the light weight and high output power of a compact gas turbine, it might be possible to realize a power density (maximum output per unit mass) and energy density (continuous operation time per unit mass) that are much higher than those of reciprocating engines and fuel cells.
IHI expects that the gas turbine generator unit will be used as a charger for personal and mobile devices as well as a power source for a robot. Future plans are to further reduce the size and weight of the unit and increase the output power plus develop technologies to comply with specifications required for various applications.
So far as your humble writer knows, IHI is the first with a prototype gas turbine connected to a generator as a kit. Both the U.S. and the UK have entrepreneurial firms working at similar goals. So it’s with great pleasure to see one get to a working prototype. When the other firms send their news I’ll be happy to spread it out too.
Turbines are external combustion and can offer more thermal efficiency than internal combustion such as piston and cylinder engines. The problem has been both size and heat dissipation that parallel requirements for exotic materials and manufacturing processes. That is balanced by fuel efficiency and very long life.
That 70ºC exhaust temp is very intriguing. No mention is made at Tech-On of the rated electrical power out, yet that and the projected pricing are very interesting facts we’ll keep an eye out for. Lets hope that the miniaturization has a beneficial impact on manufacturing costs.