VAST Power Systems, Inc. (VAST) is developing an external combustor that uses water or some other inert thermal diluent rather than air to cool combustion. This technology has allowed the demonstration (through computer simulations and empirical lab testing) of a number of significant benefits.
The following are a few of the benefits expected from the VAST technology.
|Lowered Emissions||Fuel Flexibility: from Nat. Gas to crude|
|Improved Cycle Efficiency||Wide Range of Operating Temperatures|
|Improved Economics (IRR)||Distributed Generation of Heating and CO2|
|More Power from Smaller Turbines (Increased Power Density)||Distributed Generation of CO2 for Enhanced Oil Recovery (EOR)|
VAST achieves ultra-low emissions levels using natural gas (without requiring post combustion catalytic cleanup); low single digit ppm levels for nitrogen oxides (NOx) simultaneously with low single digit carbon monoxide (CO) and unburned hydrocarbons (UBHC). The VASThermogenerator™ avoids forming pollutants during combustion so they do not have to removed afterwards. The CFD (Computational Fluid Dynamics) software simulations by Combustion Science and Engineering, Inc. of Columbia, Maryland using Star CD combustion modeling software show very encouraging results. EPA-certified stack gas testing labs have independently verified bench-scale VAST Progressive Combustion apparatus burning propane to have reached sub- 1 ppm levels for both NOX and CO.
Improved Economics (IRR)
In power generation and especially in CHP applications, VAST efficiency levels achieved during off-peak operations combined with low CapEx and O&M costs offer the prospect of improved payback benefits. Thermoeconomic analysis by a consulting team from the Power and Transportation Division of the Engineering Department of the University of Genoa, Genoa, Italy, shows CHP efficiencies for VAST that are better than STIG cycles and at CapEx costs 10% to 25% lower. VAST Cycles show the promise of Internal Rates of Return (IRR) for power generation that are markedly better than the five leading competitive cycles, especially at partial loads of 4,000 hrs/year or less.
The ability of a VASThermogenerator to better insure precise and uniform temperatures translates into lower Operating And Maintenance (O&M) costs. This cost saving is enhanced by the simplicity of the VAST combustor design.
Multi-fuel capability also enhances economic performance.
Fuel Flexibility: from Natural Gas to Crude Oil
The VAST combustor can burn multiple fuels with little adjustment. We have burned Propane, #2 Diesel, various heavy fuel oils, and Bunker Crude. Our ability to control the combustion process more effectively enables VAST to provide very precise control of both temperature and pressure to meet various process requirements. Also, this ability allows improved uniformity and thereby minimizes hot or cold spots with their accompanying problems such as NOx and CO emissions. A small bench model (0.57 MW) was built and tested in the mid 1990’s with encouraging results. In these test runs, VAST demonstrated +/- 1 degree F precision at turbine combustion temperatures. This precise and more uniform temperature and pressure controllability translates into improved equipment reliability and reduced operating costs.
We believe that the VAST technology can be utilized in many applications including
- Distributed Generation/Combined Cooling, Heat And Power (DG/CCHP)
- Enhanced Oil Recovery (EOR)
- Bitumen heating in oilsands via SAGD or CSS
- Brownfield remediation where large amounts of petroleum have been spilled
- Open ocean oil spill response equipment, especially for spills of crude oil
- Liquid and gaseous waste elimination
In all of these combustion applications, VASTech can maintain homogeneous temperature profiles or provide spatial and temporal temperature distributions to achieve optimal heating characteristics for process applications. We can easily change temperature profiles dynamically in real time. We can handle widely variable Btu rates as a result of variable off gas composition or sudden increases in heat demand or combustion intensity. VASThermogenerators have demonstrated stable combustion with ultra-low pollution profiles with primary combustion temperature ranges as low as 700 degree C. VASThermogenerators also can handle combustion temperatures over the full range of fuel combustion, though as temperatures exceed around 2,300 degrees F, NOx formation occurs in our cycle, as in any other cycle in which hot spots exceed such temperatures. The difference in the VASThermogenerator is that we can select the temperature desired and minimize, virtually eliminating any hot spots. The result is that VASTgas™, what we call the energetic working fluid created by a VASThermogenerator, has very, very low levels of pollutants in it, even without any post-combustion hot gas clean up by catalytic converter or other treatment protocol. Because of the VAST Wet Cycle and the VAST Progressive Combustion™ processes used in VASThermogenerators, VASTgas does not need post-combustion treatment to meet and exceed current air quality control standards such as those set by the South Coast Air Quality Management District (AQMD) of Southern California – the smoggiest region in the USA.
VAST has over 40 active patents issued in the U.S. and internationally, with more than 130 still in various stages of the patent pending process in each country. Over $8 million has been invested in filing over 65 independent claims with over 1,100 dependent claims in our patent portfolio.
A marketing study done for VAST by Sargent & Lundy recommended that we focus initially on the Distributed Generation market because our efficiencies are less affected by scale than are most power cycles. Our pollution control technology is also much less sensitive to scale than most power cycle pollution control technologies. This should enable the VAST Wet Combustion Power Cycle to achieve higher efficiencies and less costly pollution control than other systems operating in these lower MW size ranges. Additionally our potentially small footprint per kW would add a competitive advantage in these smaller size ranges.
Studies performed by consultants at the University of Genoa, in Italy, quantified substantial thermoeconomic advantages in the small to medium size range systems; e.g., 5 MW to 50 MW. Therefore, we welcome any opportunities to explore potential cooperation with counterparts in various sectors of the power generation market. We are now in the process of refining our computer models and preparing for further empirical lab verification in our journey toward commercialization. If you are interested in exploring the possibility of participating in this effort, we would be happy to present our technology in more detail.
VAST is an energy technology company in its R&D phase and has not yet embodied its technical solutions in specific operating equipment or processes. We do sufficiently understand the underlying combustion science and thermodynamics and have solved most of the initial engineering problems inherent in applying the VAST Wet Combustion Cycle to a Distributed Generation application. VAST Power Systems, Inc. is now beginning to seek counterparts with whom we can partner to finish the technical R&D, perform appropriate empirical verifications and CFD model parameterization. Ultimately, such a counterpart would undertake the commercialization of the VASTechnology™in those sectors of technical practice in which they see the potential for VASTech™ to further their commercial objectives.