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By Mike Millikin on Personal Transit

Posted on: Mon, Dec 26 2005  

Myers Motors has introduced its NmG (No More Gas) personal electric vehicle: a sealed lead-acid battery-powered tricycle with a top speed of 70 mph and a range of 20–40 miles.

The NMG is a direct descendant of the Corbin Sparrow, which was made at the Corbin plant from 2000 until late 2002. In March 2003 Corbin Motors filed for bankruptcy; Myers Motors resurrected the company in 2004, and completely re-engineered the entire transport system, electronics, and charging systems, while retaining the distinctive body of the Sparrow.

The NmG uses a 156V 20 kW (30 kW peak) DC Motor to drive the single rear wheel. Thirteen sealed lead-acid Optima batteries provide the power. Six are located under the front hood and the remaining 7 are under the drivers seat. The batteries recharge in four to six hours at a 110-volt, 20-amp outlet, or two to three hours at a 220-volt, 20-amp outlet. A 110-volt charger will recharge the batteries in six to eight hours.

The Optima batteries are absorption glass mat (AGM) lead-acid batteries in which the acid is absorbed by a very fine fiberglass mat between the plates and immobilized. No silica gel is necessary. With the acid absorbed and available to the plates, the glass mats allow for a fast reaction between acid and plate material.

The AGM battery has low internal electrical resistance. This, combined with faster acid migration, allows the AGM batteries to deliver and absorb higher rates of amperage than other sealed batteries during discharging and charging. In addition, AGM technology batteries can be charged at normal lead-acid regulated charging voltages and it is not necessary to recalibrate charging systems or purchase special chargers.

The three-wheeler is considered a motorcycle for the purposes of registration, insurance and parking.

The NmG offer cabin features such as power windows, AM/FM stereo and CD player, power ports for laptop and cell phone and a fan-operated heater/defroster. The trunk offers six cubic feet of storage.

 

Copy from : http://www.greencarcongress.com/2005/12/myers_motors_nm.html

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By Mike Millikin on Wind

Posted on: Wed, Dec 28 2005 11:44 AM

Rentech has been awarded a new patent (its 20th in this area) on a process for co-producing Fischer-Tropsch (FT) liquids and electrical power with CO2 emissions reduced through carbon capture.

The plant described in the patent combines an air separation unit, a syngas generator, a Fischer-Tropsch unit, a CO2 removal unit and a combined cycle electricity generation unit. Although each of these individual components are well known, Rentech is knitting the units together in its process.

The process described in the patent—Integrated Fischer-Tropsch and Power Production Plant with Low Carbon Dioxide Emissions—uses primarily hydrogen from the FT tail gas (gas that is not converted inside the FT reactor) and bypassed syngas (a combination of hydrogen and carbon monoxide (CO) produced from a hydrocarbon feedstock) to fuel the combustion turbine of a combined cycle unit.

The combined streams of FT tail gases and bypassed syngas are fed to a shift reactor in which the carbon monoxide is reacted with water to produce hydrogen and carbon dioxide (CO2). CO2 removed from the shift reactor outflow can then be used in commercial process such as chemical and fertilizer production, bottling for carbonated drinks and tertiary recovery in oil fields.

The remaining effluent from the shift reactor (mainly H2) flows to power a combustion turbine to produce electricity. Fueling the turbine with primarily hydrogen greatly reduces the amount of CO2 produced in the stack gases.

Hot exhaust gases from the turbine are cooled in a heat recovery steam turbine, which is also coupled to the generator. Exhaust steam is cooled and recirculated as process water.

Producers can opt to divide the syngas into two streams as it leaves the sulfur removal unit, with one stream going to the FT reactor, the other directly to the shift reactor. This implementation allows producers to optimize the output between FT fuels and electricity.

A computer simulation of the process yielded the following:

  • 5,550 tons per day (tpd) coal gasified with 3,091 tpd water and 4,806 tpd oxygen. The coal (Pittsburgh #8) is 74.16% by weight carbon.
  • After quenching and cleaning, 47.2% of the syngas flows to an FT reactor to produce 6,000 barrels per day of liquids and tail gases.
  • FT tail gases and the other 52.8% of the syngas are mixed with 233 MMSCFD of steam and sent to a low-temperature shift reactor.
  • Gases leaving the shift reactor are on a volume basis approximately 38.0% hydrogen, 37.5% CO2, 23.0% H2O and less than 1% of CO, CH4 and N2.
  • Carbon capture removes 11,300 tpd of CO2.
  • The H2-rich gas used as fuel in the combustor produces approximately 349 Mwe in the combined cycle unit.
  • 3.5% by weight of the carbon in the coal fed to the gasifier is present in the flue gases emitted into the atmosphere.

Resources:

Copy from : http://www.greencarcongress.com/2005/12/rentech_awarded.html

Technology Characterisation
of the Hydrogen Economy

Mike Hodson and Simon Marvin,
Centre for Sustainable Urban and Regional Futures (SURF), University of Salford

WORKING PAPER 1, May 2004

Summary Information:


Type of study: Tyndall Centre Working Paper. One of three documents from phase
one of the Tyndall Centre project: ‘The Hydrogen Energy Economy: Its Long Term
Role in Greenhouse Gas Reduction’.
www.tyndall.ac.uk/publications/working_papers/wp17.pdf
Methodology (if specified): Largely unspecified, but draws on secondary literature
and on three sources in particular:
Lakeman and Browning (2001): Global Status of Hydrogen Research carried out by
DERA for the DTI ‘and which includes a state of the art overview of hydrogen energy
technologies’.
www.dti.gov.uk/energy/renewables/publications/pdfs/F0300239.pdf
Padró and Putsche (1999): Survey of the economics of hydrogen technologies carried
out by NREL for the US Department of Energy ‘and which includes an attempt to produced levelised cost comparisons for the major production and distribution
technologies’.
www.eere.energy.gov/hydrogenandfuelcells/pdfs/27079.pdf

 

download this paper at :

http://www.surf.salford.ac.uk/documents/%20Supergen/SURF_Hydrogen_WorkingPaper1_May2004.pdf

A HYDROGEN FUTURE?
An Economic and Environmental Assessment of Hydrogen Production Pathways

Authors
Antonia Herzog, Natural Resources Defense Council
Marika Tatsutani, Consultant

Natural Resources Defense Council
issue paper: november 2005

 

CONCLUSION AND POLICY RECOMMENDATIONS

The results of this preliminary assessment highlight a number of significant issues that must be resolved before hydrogen can play a substantial role in addressing the nation’s and the world’s energy security and global warming challenges. Central among these is the fact that the least expensive and most mature hydrogen production pathways available at present are not necessarily environmentally sustainable. For example, one of the cheaper options available today—producing hydrogen from coal—will not be acceptable unless associated global warming, air pollution, and mining impacts are successfully addressed. The deployment of coal gasification technology with carbon capture and storage, in combination with mining practices that minimize land and water impacts, could allow coal to become a sustainable and abundant source of hydrogen over the long term, both in the United States and in other coal-rich countries. However, further aggressive deployment of advanced coal gasification technologies, in combination with carbon capture and storage, is needed to better determine the cost, feasibility, and effectiveness of this potential hydrogen production pathway.

Hydrogen production from natural gas, meanwhile, offers a number of near-term advantages in terms of cost and technological maturity, but it too can prove problematic as a longer-term solution. Because natural gas, like coal, is a fossil fuel, its use as a hydrogen feedstock generates pollutant emissions that contribute to global warming and air quality problems. Data presented in this report (see Figure 1) indicate that per-mile global warming emissions for a fuel cell vehicle running on hydrogen produced using various forms of steam methane reformation are anywhere from 40 percent to 50 percent lower than emissions for a conventional vehicle running on reformulated gasoline. These emissions reductions are not trivial—but it is also the case that comparable global warming benefits could be achieved by simply deploying efficient hybrid-electric and conventional technologies that are already available today. Moreover, high natural gas prices and supply constraints have recently emerged as serious issues that show no signs of being resolved soon, at least in North America.

Thus, natural gas is probably best thought of as a potential transition fuel to cleaner, low-carbon, domestic hydrogen production options, such as renewables or coal with carbon capture and storage. Given the extensive natural gas infrastructure that already exists, use of this feedstock may make sense in the early stages of a possible future shift to hydrogen but even then, natural gas should only be considered in the context of an alternative longerterm hydrogen production strategy, with care taken to address technological lock-in concerns, wherein an inappropriate technology is deployed too early, thereby preventing a better technology from emerging as the longer term solution. Additionally, distributed production from natural gas using small-scale steam methane reformers— because it obviates the need for hydrogen transport—is also an attractive short-term production option, but it is important to keep in mind that this option does not easily allow for eventual carbon capture and storage. Meanwhile, to alleviate supply constraints that might otherwise preclude the use of natural gas as a transition fuel for producing hydrogen, natural gas demand growth should be addressed through improvements in the end-use efficiency of gas equipment; and through the increased use of combined heat and power and other distributed or high-efficiency technologies.

Compared to coal- or natural gas-based production pathways, hydrogen from nuclear energy could offer some advantages in terms of global warming emissions. However, cost estimates of hydrogen production at future…………………….

 

Download this paper at : www.nrdc.org/air/transportation/hydrogen/hydrogen.pdf