- July
Posted By : Sarah Ravhudzulo
Gate 5 Energy System

FinnZa – Gate 5

Brief Technology Description

The Gate 5 Energy System (G5ES) is a highly scalable carbon neutral, thermal, non-incineration, process that can efficiently keep a variety of biomass and waste, namely; sewage sludge, fecal material, food waste and animal manure (together called “residuals”) out of the environment by transforming the residuals into renewable energy, potable water and other usable by-products without using fossil fuel or grid electricity. The G5ES dries and mills residuals into a finely powdered biofuel that is combusted in a biomass boiler. The heat produced in the process powers a turbine that generates continuously available renewable electricity in excess of the G5ES’s parasitic energy load.

Next Steps Required

FinnZa/Gate 5 want to prove the G5ES technology in South Africa and need to partner up with a wastewater treatment plant or industry producing problem waste with high calorific value, as well as potential financial partners. The first unit in South Africa will be build on a trailer in order to be mobile and will be able to be moved between test locations.  The G5ES will be manufactured in South Africa under license form Gate 5 Energy Partners and this unit can be as small as handling 7 wet tonnes per day, with no upper limit.

Key Personnel

Gate 5 Energy:

Steve Delson – Chief Executive Officer
Jon Glazer –  Chief Financial Officer
George Kladnik – Dir. Strategic Planning


Gregory Neethling, Managing Director

Company Background

It is a collaboration between two companies. FinnZa is a South African owned company operating in the renewable energy sector in Southern Africa. FinnZa and Gate 5 Energy Partners, Inc. are working to finalize an exclusive license for the use of Gate 5’s sustainable energy infrastructure in South Africa. Gate 5 Energy Partners, Inc. of Irvine, California, USA has been developing the live changing Gate 5 Energy System over many years and are now ready to roll out this technology worldwide.

Detailed Technology Description

  • The G5ES is an innovative integration of sustainable management of residuals with on-site energy production that runs without using any fossil or other fuels, on (self-sustaining) energy recovered solely from these combusted residuals. The patented Gate 5 technology will efficiently transform 100% of these residuals into valuable by-products: renewable electrical and thermal energy, clean water, and ash. The process employs a circular dryer with no internal moving parts that dry and pulverizes the residuals into a powdered biofuel; followed by a conventional combustion system, adapted from the coal industry for steam generation; and a turbine for electric power production.

The diagram illustrates a G5ES treating biosolids at a WWTP employing anaerobic digestion. However, the preferred feedstock for the G5ES would be primary sludge/WAS, which would produce significantly more sustainable energy than biosolids because of its higher latent energy content (~ 2x). The G5ES can easily be configured to operate on primary and waste activated sludge (WAS) alone or in combination with other residuals.


  • A live-bottom silo, sized to provide adequate volume of material so the G5ES can produce renewable energy and operate on a 24/7 basis holds the feedstock
  • Screening of feedstock as it enters the silo keep oversized and “trash-like” material from the G5ES (not used with biosolids)
  • A screw-drive delivery system will prevent the feedstock from being compacted into a cake-like material that would be difficult to dry


  • The flash/ring dryer utilized in the G5ES has no moving parts and is capable of continuously producing biofuel from dewatered sewage sludge, biosolids, food waste or manure [1]
  • Moist high-temperature (<600 F) drying gas absorbs the moisture in the feedstock and particles collide to pulverize the feedstock into a finely powdered and dried biofuel that is delivered to the energy recovery cycle
  • A gas-solids separator and cyclone equipment processes the post-dryer vapor into usable distilled water (<200 gallons per ton) from the prepared feedstock.
  • The drying gas is reheated in the boiler; mixed with combusted waste heat from the boiler (see below); and then circulated back to the dryer (Waste heat from the drying cycle may also be used to heat a WWTP digester, thereby saving a WWTP the need for a separate digester heating system)

Energy Recovery

  • 100-percent of biofuel produced from the drying cycle is combusted at a temperature >2,000oF in a biomass boiler (assuring complete destruction of all organics in the residuals)
  • Steam heated by the combusted biofuel is utilized in a turbine to produce the power to run the G5ES and, in cases where there is not sufficient waste heat for the drying process, to heat the drying gas
  • Combusted air is cleaned by separating the remaining inert ash and water from the air and scrubbing the air with pollution control equipment to meet applicable air quality standards before it is discharged [2]
  • Ash is the inert solid that remains after the combustion of the biofuel and also includes the non-volatile inorganics material that was in the system’s feedstock [3]

Sustainable Power Production

  • A steam turbine, and in some cases an organic Rankine cycle (ORC) turbine, will run on heat produced in the G5ES boiler
  • Solar heat collectors installed on the G5ES canopy can increase renewable power production by between 200 kW and 300 kW where project size and the particular location and microclimate will justify the additional expense
  • The waste heat from the turbine(s) can be used to heat the digesters as well as satisfy other heated water needs of the customer or community
  • G5ESs configured to run with anaerobic digested sludge (biosolids) and digester gas are estimated to produce gross and surplus renewable energy production as follows:

Technology Applications

Water treatment plants where sludge is accumulated.


  • The circular dryer system has produced powdered biofuel (<72 microns particle size and 90% solids)
  • Biofuel combusted using powered fuel burner (temperature > 1000OC)
  • Synthetic and organic compounds of concern are destroyed in the G5ES
  • Potable water is a by-product ~ 950 litres from each wet ton of sludge
  • Can produce 81kW of renewable electricity from 2 wet ton of sludge

Testing and Demonstration Results

Although there is no operational G5ES today, the design has undergone rigorous evaluation by multiple third-parties and has been confirmed by letter dated December 16, 2011 from Crystal Presley-Willis of the California Energy Commission, which in 2011 accepted Gate 5’s technology as “appropriate for industrial demonstration” (see appendix). The following summaries of G5ES technology assessments are provided:

  • The G5ES’s initial proof of concept was developed for a 72 WTPD System and is described in SERT Inventor’s 2011 paper (*1)
  •  HDR Engineering, Inc. (“HDR”) has been involved in the early stage design of the G5ES since spring of 2011 and supports that the System is ready for commercial installation (*2)
  • ·Heat Transfer Solutions, Inc. (“HTS” as previously defined) has provided additional proof of concept and peer review papers noting that the design is ready for implementation on a commercial scale (*3)
  • ·Fuel drying was performed in March 2012 at the dryer manufacturer’s facilities on the U.S. east coast
  •  Hazen Research, Columbia Analytical Labs, and Republic Environmental Systems have each performed multiple lab and bench scale tests on the fuel that confirm the suitability of its Btu content and combustibility for the G5ES
  • An early advisor assisting the development of the technology, Dr. Scott Samuelsen from UCI’s APEP pronounced the G5ES ready for commercial scale implementation in late 2011. (*4)
  • Dr. Ashok Rao from APEP, who performed rigorous heat balance and energy balance analyses through the summer of 2012 that have led to additional innovation and system refinements to produce a design that will recover and use more than 93 percent of the energy that enters the process.  (*5)
  • The Mitigated Negative Declaration for the construction of the initial G5ES (Lead Agency: Santa Margarita Water District in Orange County, CA) confirms that the G5ES’s air quality and health-risks issues are within acceptable limits (California State Clearinghouse number is 2013071095)

Papers and Publications

  • Steve Delson, George A. Kladnik , MIchael D. Moore. 2016. “Sustainable Biomass Combustion Infrastructure for Optimal Energy Recovery”. 6th international symposium on energy from biomass and waste.

IP Status

Two patents listed in both Australia and New Zealand and another patent pending in U.S., Europe, Australia and New Zealand.

website Finnza

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