SPR Ltd.


The EmDrive

A New Concept in Spacecraft Propulsion

Satellite Propulsion Research Ltd (SPR Ltd) a small UK based company, has demonstrated a remarkable new space propulsion technology. The company has successfully tested both an experimental thruster and a demonstrator engine which use patented microwave technology to convert electrical energy directly into thrust. No propellant is used in the conversion process. Thrust is produced by the amplification of the radiation pressure of an electromagnetic wave propagated through a resonant waveguide assembly.

Contact sprltd@emdrive.com

Latest news

June 2017

An edited set of slides from a presentation made to the UK Defence Academy in February this year can be downloaded here. They give the background story to the emergence of EmDrive, and illustrate how important Global Defence applications are to the continuing development of the technology.

Shrivenham Presentation

September 2016

A slide presentation with narration, explaining the basic science behind EmDrive can be downloaded here.


August 2016

Development work is continuing on superconducting EmDrive thruster technology in co-operation with a UK aerospace company. No details of this work can be divulged at present.

However, as it is now 10 years since the completion of the original research work, the documents reporting on this work can be released, and can be accessed here.

Feasibility study technical report. Issue 2

Review of experimental thruster report

Demonstrator technical report. Issue 2

Review of DM tech report

The documents are two final technical reports and two independent reviews, and date from July 2002 to August 2006. The work was carried out for the UK government under their SMART and R&D award programmes. Documentation was shared with US government organisations.

The research was carried out concurrently with the BAE Systems Greenglow project, which was the subject of a BBC Horizon programme broadcast in March this year.

July 2015

A peer reviewed version of the IAC14 conference paper is given here: IAC14 Paper

A 5 minute audioslide presentation of the IAC14 paper, updated to include the latest test data from the University of Dresden Germany, is given here: IAC14 Audioslide (.avi 11MB)

June 2015

The full test video of one of the dynamic test runs of the Demonstrator engine has been released and is available here: Dynamic Test (.mpg 43MB) or Dynamic Test (.avi 112MB)

Notes giving an explanation of the test rig and this particular test run are given here: Notes on Dynamic Test

May 2015

A recent interview with Roger Shawyer, filmed by Nick Breeze, can be found here: 2015 Interview

January 2015

A number of research groups have asked questions on the methods of measuring EmDrive forces. A note explaining the principles can be found here: EmDrive Force Measurement

October 2014

At the IAC 2014 conference in Toronto, Roger Shawyer stated that 8 sets of test data have now verified EmDrive theory. These data sets resulted from thrust measurements on 7 different thrusters, by 4 independent organisations, in 3 different countries.
The Toronto presentation can be found here: IAC14 Presentation

August 2014

A recent interview with Roger Shawyer, recorded by Nick Breeze at the Royal Institution in London can be found here: Interview It is accompanied by a PowerPoint presentation entitled “EmDrive-Enabling a Better Future”.

July 2014

A paper entitled "Second Generation EmDrive Propulsion Applied to SSTO Launcher and Interstellar Probe" will be presented at the 65th International Astronautical Congress 2014 at Toronto in September.

October 2013

A paper entitled "The Dynamic Operation of a High Q EmDrive Microwave Thruster" and the associated poster for the recent IAC13 conference in Beijing is given here: IAC13 PaperIAC13 Poster

November 2012

China publishes high power test results

The prestigious Chinese Academy of Sciences has published a paper by Professor Yang Juan confirming their high power test results. At an input power of 2.5kW, their 2.45GHz EmDrive thruster provides 720mN of thrust. The results have clearly been subject to extensive peer review following the NWPU 2010 paper. The measurements were made on a national standard, thrust measurement device, used for Ion Engine development. Details of the measurement system and calibration data are given in the paper. A professional English translation is given here: Yang Juan 2012 paper

September 2012

A solution to the acceleration limitation of superconducting EmDrive engines has been found. The application of this breakthrough has been described at a recent presentation, where a hybrid spaceplane provides a dramatic reduction in launch cost to geostationary orbit. A reduction factor of 130 compared to Atlas V launch costs is predicted. This will lead to Solar Power Satellites becoming a low cost, baseload, energy source. The presentation can be downloaded here: 2G update

July 2012

An English translation of the 2010 Chinese paper, together with unpublished test results have been obtained. The last line of the paper confirms that experimental thrust measurements have been made at 1kW input power. The unpublished test results show a large number of thrust measurements at input powers up to 2.5kW. The mean specific thrust obtained is close to that measured in the SPR flight thruster tests.

Note that the Chinese thruster, if deployed on the ISS, would easily provide the necessary delta V to compensate for orbital decay, thus eliminating the need for the reboost/refueling missions.

The original 2010 paper, the translation and the unpublished test results are given here:

NWPU 2010 paper

NWPU 2010 paper (English translation)

NWPU 2010 unpublished test results

June 2011

Two papers have been identified, published by Professor Yang Juan of The North Western Polytechnical University, Xi'an, China. These papers provide an independent proof of the theory of EmDrive. Abstracts of these papers are given in Chinese Paper Abstracts. The originals are written in Chinese.

August 2010

A Technology Transfer contract with a major US aerospace company was successfully completed. This 10 month contract was carried out under a UK Export Licence and a TAA issued by the US State Department. Details are subject to ITAR regulations.

June 2010

A paper was presented at the 2nd Conference on Disruptive Technology in Space Activities. See: Toulouse 2010 Paper

Earlier papers presented in a series of international conferences were:

Brighton 2005 paper

IAC 2008 paper

CEAS 2009 paper

May 2010

The Flight Thruster test programme was successfully completed. See: Flight Programme