April 30, 2006
Bosch Backs Tidal Power Project
|The Rotech Tidal Turbine|
Bosch Rexroth, the drive, control and linear motion specialty subsidiary of the Bosch Group, is working with UK firms Lunar Energy and Rotech on a prototype tidal turbine for a tidal power project to be tested this year off the Orkney Islands.
Rotech, a specialist in tools for the oil & gas, geothermal, subsea and renewable energy markets, developed the bi-directional Rotech Tidal Turbine (RTT) that has been exclusively licensed to Lunar Energy. Rexroth is providing the scale of equipment needed to bring the concept from small scale water tank model to prototype scale.
Power is generated from tidal water movement that flows through the turbine which turns a large fixed-displacement hydrostatic pump to produce hydraulic pressure and flow.
The hydraulic flow and pressure varies with the state of the tidal stream, from minute to minute, due to the nature of the hydrodynamics of the location of the turbine. The turbine also reverses direction when the tidal flow reverses as it does twice a day.
The output to drive the generator is needs to be at a constant speed and direction. Rexroth provides a duel overcenter swash plate axial piston motor to carry out this task of converting the flow and pressure into mechanical shaft power.
The duct captures a large area of the tidal stream and accelerates the flow through a narrowing channel into the turbine. Thus, a smaller turbine can be used for a given power output, or alternatively, a larger amount of power can be generated by a turbine of given blade diameter.
The capability for bi-directional operation obviates the need for a pitch or yaw control thus keeping the design simple and more cost effective. Tidal flow can be offset by as much as 40 degrees to the duct axis without affecting the performance. In fact, when operating in flows that come from this ±40 degree sector, the ducted system extracts more power than when the flow is perfectly aligned with the turbine axis.
The bi-directional turbines, each weighing about 1,000 tonnes, will be mounted on the seabed. The core elements of the RTT are a large bi-directional venturi casing with an inlet diameter of 21m, narrowing to 14m, and a five-bladed fixed-pitch propeller of innovative blade form. All components are to be designed for a four-year maintenance period.
The prototype unit, designed to produce about 1MW of power, will be placed on the seabed off the Orkney Islands during Summer 2006.
The Orkney tidal power project is backed by a £5-million (US$9.2-million) grant from the Department of Trade and Industry.
Rexroth is also a prime supplier to the major wind turbine manufacturers. The company is also working on hydraulic hybrid drive components.
Increasing Number of Cars in Delhi Undoing Clean Air Gains; A Call to “Reverse Automobile Dependence”
|More than half of the Indian cities monitored during 2004 recorded critical levels of PM10. Click to enlarge.|
The increasing number of private vehicles in Delhi is putting the city at risk of losing its hard-won gains in cleaner air, according to a new publication from the Centre for Science and Environment (CSE).
The new publication, The Leapfrog Factor: Clearing the air in Asian cities, also notes that an increasing number of Indian cities, a number of which are small, non-metropolitan entities, are turning into “smog-encased pollution hotspots.”
Delhi would have been buried under a pollution load of 38% more particulates if the Supreme Court had not intervened to introduce cleaner fuels and emissions technology in the city, such as introducing CNG for city buses.
The city has seen the introduction of some 100,000 CNG vehicles within a span of five years, and currently has the largest CNG public transport fleet: 10,600 CNG buses. The city has also improved fuel quality with low sulfur and benzene limits, and introduced Euro-3 emissions requirements in 2005.
But, according to Anumita Roychowdhury, associate director, CSE and head of CSE’s Right to Clean Air campaign:
The most worrying trend in Delhi is that while the technology roadmap remains sluggish, the sheer numbers of vehicles are overpowering the change. Unbelievably, as much as 17 per cent of the cars in India run in Delhi alone. It has more cars than the total numbers of cars in the individual states of Maharashtra, Tamil Nadu, Gujarat and West Bengal.
The congestion and pollution crisis is building up not only in Delhi, but in all Indian cities because a large share of daily travel trips is being made by personal transport, according to the report. A car caught in congestion can early quadruple its emissions. Cars and two-wheelers take up nearly 90%, carry fewer numbers of people and pollute excessively.
As a result, according to the authors, public transport is collapsing in most cities. Only eight of the 35 cities that have more than a million population have dedicated bus services; even these are under extreme pressure. While India’s metro cities need to support approximately 80 million trips daily, the available rail and bus transport can support only 37 million.
Although some of India’s larger cities have seen a decline in their pollution levels, as many as 57% of all the cities monitored in the country have critical PM10 levels (more than 1.5 times the standards). Newer and smaller cities are more polluted than even the metros.
The health impacts are enormous. Each year, according to the World Health Organization, air pollution accounts for 0.8 million deaths and 4.6 million lost life-years worldwide; two-third of this occurs in developing Asian countries, and India alone accounts for more than 0.1 million premature deaths annually.
|India’s metro PM and NOx standards relative to US, EU and Japan. Click to enlarge.|
Two-wheelers and increasing dieselization pose significant challenges for India, especially given the relative laxity of the country&rquo;s emissions requirements for passenger vehicles. Diesel vehicles will dominate nearly 50% of new car sales in the country by 2010, according to the report.
Although India has some of the strictest emissions standards in the world for two-wheelers, a new two-wheeler in India emits 1.5 times more CO and 8 times more HC+NOx than and new Euro-4 in Europe.
The only way out, according to CSE, is to “reinvent the idea of mobility.” Accordingly the publication makes a series of policy recommendations:
Implement radical solutions within a short time-frame for long-term gains.
Cities should base themselves on public transport, and manage their mobility by restricting cars.
Leapfrog to cleaner vehicle technologies and fuels to cut exposure to toxic fumes.
Introduce fuel economy standards to improve energy efficiency of vehicles.
Use fiscal incentives for propelling change.
The Leapfrog Factor: Clearing the air in Asian cities (Presentation)
April 29, 2006
Ford Talks Up Sustainability at LOHAS 2006; Investigating Plug-In Hybrids
by Jack Rosebro
|Escape Hybrid at LOHAS 10.|
Yesterday, Ford Motor Company’s Niel Golightly, the automaker’s director of sustainable business strategies, presented some of Ford’s recent initiatives toward sustainability at the LOHAS 10 (Lifestyles of Health and Sustainability) conference in Santa Monica.
Ford is a major sponsor of the event, and several of Ford’s Escape hybrids were prominently displayed on the conference grounds.
Asserting his faith in the future, Golightly said, “Some people say that the auto industry will go the way of the fur coat or cigarette industries. I’m here to tell you that it won’t happen. People need cars. People need mobility.”
He acknowledged, however, that automakers, including Ford, are starting to “feel the pull” toward sustainability from many sources, such as energy costs, customers, and institutional investors.
The day is coming when customers will no more accept a car that produces greenhouse gases, is made from nonrenewable resources, or is made by exploited workers than they would accept a car without seatbelts.—Niel Golightly
Ford’s sustainability chief then introduced the audience to a pair of environmental initiatives: a partnership with TerraPass to market carbon offsets to owners and operators of Ford products (earlier post), and the introduction of renewable and recyclable seat fabrics to 80,000 as-yet unnamed Ford vehicles as of model-year 2007. Ford also plans to increase the recycled content of each vehicle’s interior to 25% whenever that vehicle is redesigned.
Terrapass offers Ford, Lincoln, and Mercury drivers the use of a carbon offset calculator to find out how much carbon dioxide their particular vehicle produces, as well as the effects of actions such as removing a roof rack or properly inflating the vehicle’s tires.
The energy sources for the carbon offsets are a wind farm in Nebraska and a methane digester at a dairy farm in Minnesota. Ford will promote the program with a point-of-purchase marketing campaign called Greener Miles.
The recyclable seat fabrics were developed by Interface, Inc., a major carpet and fabric manufacturer. According to a representative of Interface, the fabrics are made from “post-industrial waste”: fossil-fuel based plastics which do not meet top-tier quality guidelines for products such as soda bottles, and which are then sold to a secondary market.
Interface is reportedly investigating plant-based fibers from renewable sources; DaimlerChrysler and Honda have already begun to use such materials.
Interface began to focus on sustainability in 1994 after its chairman, Ray Anderson, read Paul Hawken’s seminal book, The Ecology of Commerce. Anderson later reflected, “For the first twenty-one years of Interface’s existence, I never gave one thought to what we took from or did to the Earth, except to be sure we obeyed all laws and regulations...Frankly, I didn’t have a vision, except ‘comply, comply, comply.’”
Interface is also one of the first US corporations to adopt The Natural Step, a science-and systems-based sustainability framework that is used by a growing collection of communities and corporations worldwide.
The Natural Step, or TNS, defines a sustainable world by the achievement of four system conditions, three of which are environmental and one that is socioeconomic. TNS uses techniques such as “backcasting” to envision a sustainable future, and then work backward toward the present from that future.
In a subsequent interview with Green Car Congress, Golightly acknowledged an awareness of The Natural Step, in part through his work with Interface. Golightly candidly stated that Ford’s definition of sustainability is very much a work in progress, and that in the future, new tools will be needed to address larger problems such as the predicted doubling of the world’s vehicle fleet within a generation, or the growth of a corporation’s total greenhouse gas production as a result of its economic expansion.
These are tough issues, and the wisdom of a constantly growing economy in a finite world has been questioned before, most notably in the 1970s. However, there is a renewed interest in limits to growth, and in the associated field of ecological economics.
Readers of our recent series on automakers’ sustainability reports here at Green Car Congress may also recall that Ford’s 2005 sustainability report defines sustainable development in economic, environmental, and social terms, and defined social capital as “the capacity of people in our communities to participate fully in both the production and consumption of our products and services.”
When questioned about such a definition, Golightly explained that it is a working definition limited by the company’s ability to influence “what we [Ford] can put our hands on.”
Plug-ins. Golightly also touched on the prospect of Ford-built plug-in hybrids, saying that the company is investigating the technology, but that three “significant issues” remain as barriers to production: battery life, warranty coverage, and safety.
It is likely that the first production plug-in hybrids will use lithium-ion (Li-ion) battery packs. However, Li-ion batteries are generally considered to be less stable than nickel-metal hydride, the current hybrid battery of choice. Much of the development of Li-ion batteries is focused on addressing those concerns.
In a subsequent breakout session at the conference, another Ford representative assured attendees that “the message [about plug-in hybrids] is coming through loud and clear.”
Addressing a question about Toronto-based HyMotion’s conversion of Ford’s Escape hybrids to plug-in hybrids (earlier post), the representative said that “we encourage our customers to be creative with our cars.”
Santa Monica’s LOHAS event was the tenth such conference presented in the US. Originally focused on personal care and health products, it is beginning to broaden its focus to sustainability in general. Although the popularity of the LOHAS acronym is growing in the US, it is by far more widely used and recognized in Japan than in other parts of the world.
Diester Contracts Another Esterfip-H Biodiesel Plant from Technip
|The dual-reactor Esterfip-H process flow diagram.|
Diester Industrie, the French biodiesel pioneer, has awarded Technip, one of the top five global providers of full-service engineering and construction services in the hydrocarbons and petrochemicals industries, a turnkey contract for another new biodiesel plant based on the Axens Esterfip-H process. The plant will be built in Montoir-de-Bretagne, near Saint Nazaire, France.
The new plant, with a future capacity of 250,000 tonnes per year (75.5 million gallons US per year), will come online in the spring of 2007. In January, Diester contracted with Technip for a new 100,000-tonnes/year biodiesel unit (about 30.2 million gallons US) expansion of another diesel plant, again using the Esterfip-H process. (Earlier post.)
The latest project is the fourth between Technip and Diester Industrie.
The Esterfip process was developed by the French Institute of Petroleum (IFP) and commercialized by Axens. The current process, Esterfip-H (also developed by IFP), uses a heterogeneous catalyst (the “H”)—a spinel mixed oxide of two (non-noble) metals.
|Heterogeneous Esterfip-H process requires neither catalyst recovery nor aqueous treatment steps.|
The use of heterogeneous catalysts eliminates the need for catalyst recovery and washing steps—and associated waste streams—required by processes using homogeneous catalysts such as sodium hydroxide or sodium methylate.
The dual fixed-bed reactor Esterfip-H process is based on a solid catalyst, and continuous. It produces glycerol with extremely high purity of >98%, and a very high ester yield of close to 100%.
There is no waste production of low-value fatty acids, no water saline streams requiring disposal, and no consumption or handling of chemicals. It also features a lower catalyst requirements per ton of biodiesel produced than other processes.
The Esterfip-H process has been chosen recently for two other large biodiesel projects: the 165,000-tonnes/year (50 million gallons US) Beatrice Biodiesel plant in Nebraska; and the Perstorp Oxo 160,000-tonnes/year plant in Sweden.
IFP video on Esterflip-H
April 28, 2006
Portland, Maine, METRO adds CNG to Transit Fleet
|John Deere 6081H CNG engine|
Portland, Maine, METRO is introducing CNG to its fleet with the addition of 13 new CNG-powered transit buses and a CNG refueling station. The natural gas fueling station will also be used by the Portland School Department and made available to fuel other vehicles that use natural gas.
The Orion VII buses use the 6081H 6-cylinder, 8.0-liter turbocharged natural gas engine from John Deere, which delivers 280 hp (209 kW) of power at 2,200 rpm and 1,220 Nm of torque at 1,500 rpm.
The 6081H is also available for Liquefied Natural Gas (LNG), and has been certified to US Environmental Protection Agency (EPA) emissions levels and California Air Resources Board (CARB) optional low NOx standards 1.2 g/bhp-hr for MHHD, HHDD, and urban bus vehicles.
John Deere Power Systems will offer a 9.0-liter natural gas engine, which will be available in 2007 and will be certified to 2010 emissions levels of 0.2 g/bhp-hr for MHHD, HHDD, and urban bus vehicles. This engine offers an expanded power range of 250 hp–300+ hp and a peak torque of 1,050 ft-lbs at the maximum rating, which will help optimize vehicle low-end performance. The 9.0L engine will be also available in compressed natural gas or liquid natural gas.
The METRO, with a fleet of 28 buses, has annual ridership averaging 1.3 million and is Maine’s largest public transportation carrier.
Senators Propose $100 Rebate to Offset Gas Prices; $2.9 Billion in Funding for Cellulosic Biofuels, Batteries and Plug-ins
The amendment, co-sponsored by Senators Ted Stevens (R-AK) and Charles Grassley (R-IA, and Chairman of the Senate Finance Committee), would provide a $100 rebate to each taxpayer to offset the increased price of gasoline.
Other transportation-related amendments to the bill include:
An anti price-gouging measure that makes it unlawful to increase the price of gasoline or diesel “by an unconscionable amount” within an area covered by an emergency proclamation while the proclamation is in effect. The President may issue the emergency proclamation for any area within the US, and the chief executive officer of any State may issue an emergency proclamation for any such area within that State;
Repealing the limitations on the number of hybrid and diesel vehicles eligible for tax rebates;
Authorizing the DOT to reform the fuel economy standards for passenger vehicles (earlier post);
Increasing the production incentives for cellulosic biofuels from the $250 million specified in the Energy Policy Act of 2005 to a total of $1.1 billion from fiscal year 2007 through fiscal year 2011.
Providing $1.8 billion in funding from fiscal 2007 through fiscal 2012 ($300 million each year) to accelerate development and commercialization of battery and electric drivetrain technologies for hybrids, plug-in engine hybrids and plug-in fuel-cell hybrids;
Suspending crude oil deposits into the Strategic Petroleum Reserve for 6 months;
Opening the Arctic National Wildlife Refuge up for oil and gas exploration and production.
Text of amendments
Motiva Moving Ahead on 325,000 Barrel-per-Day Refinery Expansion in US
Motiva Enterprises LLC—a joint venture between Shell and Saudi Refining Inc.—announced that it has made significant progress toward expanding refining capacity in the United States. The company has completed initial project scoping and process design for a potential 325,000-barrel-per-day crude throughput increase at the Motiva Port Arthur Refinery in Texas.
The project would more than double the current 275,000 barrel-per-day capacity of the Port Arthur Refinery—originally built in 1903 as Texaco’s first refinery—to make it the largest in the US.
Pending regulatory approvals, Motiva would expect to initiate final engineering later in 2006 and begin construction in 2007. The new capacity would be projected to come online in 2010.
We are confident that the market fundamentals will support an expansion of our US refining capacity. Adding 325,000 barrels-per-day of refining capacity would be the equivalent of building a new refinery in the United States.—William B. Welte, Motiva President and CEO
The Shell-Saudi partnership runs two other Gulf Coast refineries, both in Louisiana: the Convent Refinery with a capacity of 225,000 barrels of crude oil daily and the Norco Refinery with a capacity of 240,000 barrels per day.
TriMet Increases Transit Use of Biodiesel
TriMet, the transit agency for the three-county area around Portland, Oregon, is expanding the use of a B5 (5% biodiesel) blend to all 210 LIFT buses that provide door-to-door service for elderly and people with disabilities.
The agency had first run a four-month test of the biodiesel blend in 75 of the LIFT fleet buses starting in December, 2005—its first biodiesel initiative. The B5 blend performed well through the trial period, particularly in cold weather conditions, according to TriMet.
TriMet will require 3,500 gallons of pure biodiesel a month for the blending, which is done by Carson Oil. LIFT buses provided approximately one million rides last year.
SeQuential Pacific Biodiesel, the first local biodiesel manufacturer in Oregon, produces the B100 from vegetable oil and used cooking oil. (Earlier post.)
TriMet’s expanding use of biodiesel is helping to build a local industry that is environmentally friendly and helps us become more sustainable.—Fred Hansen, TriMet General Manager
New System for Efficient Cooling of Hybrid Drivetrains
|ORNL R134a integrated cooling system with floating loop. Click to enlarge.|
Researchers at the National Transportation Research Center, part of the Department of Energy’s Oak Ridge National Laboratory (ORNL), are developing a new approach to cooling the power electronics and motors of hybrids that could lead to better performance, improved fuel efficiency, and increased power density for future systems.
Called the Floating Loop, the new cooling system is a low pressure drop R134a refrigerant loop for direct-contact cooling. The loop shares some components and piping of the vehicle air conditioning system, but remains operationally independent. The floating loop requires only a small pump to move the liquid refrigerant.
Floating Loop is geared toward future developments of hybrid and possibly fuel cell vehicles, which will have high power, high heat-producing electronics and motors. The floating loop will enhance their operation by being able to cool these electronics and motors more efficiently.
As you more efficiently cool them, you can reduce the size, weight and volume, and that leads to greatly improved gas mileage.—Laura Marlino, ORNL Project Manager
Removing the heat generated by the electrical systems in hybrids is essential for their reliable operation and to the ability of automakers to increase power density and decrease weight and volume in future hybrid drivetrains. With improved cooling, a motor can run at a higher efficiency due to decreased resistance losses in the windings.
Hybrids currently on the market are using a variety of solutions for cooling their power electronics and traction motors, including radiator coolant loops, forced and natural air convection, and oil circulation.
The Floating Loop provides effective two-phase cooling directly for the inverter and traction motor. The system takes liquid refrigerant directly from the condenser (60°–80°C). The small pump circulates the fluid to the electronics and motor loads. where it cools the loads via evaporative cooling and direct contact. Vapor returns to the condenser. Heat is rejected to ambient by condensing the vapor from the floating loop and the passenger A/C sub systems.
Defining the Coefficient of Performance (COP) of a cooling system as the Heat Rejected divided by Input Power, the COP of the floating loop is very high (~45) (based on initial testing of a prototype system) compared to a passenger AC system (~3).
Whereas the AC system requires high input power due to high compressor pumping power, the Floating Loop uses very low pumping power to circulate the coolant through the loop.
ORNL sees the new system as applicable for a range of hybrid applications: assist-only electric motors (parallel-configuration), full hybrid traction drives (series, parallel, and series-parallel configurations) and eventually fuel cell hybrids (series configuration).
The loop concept is not dependent on R134a (which has 1,300 times the greenhouse effect as CO2, according to the DOE). ORNL is exploring the use of new AC cooling fluids.
A Compact Brayton-Cycle Engine and Biomass Process for Mixed-Alcohol Fuels
|The StarRotor compact Brayton cycle engine.|
A Texas A&M chemical engineering professor has developed a process to convert biomass to a mixed alcohol fuel that contains more energy than fuel ethanol. He has also developed a compact Brayton-cycle engine (the same thermodynamic cycle employed by jet engines) capable of being powered by any type of fuel—including his MixAlco mixed alcohol fuel.
Prof. Mark Holtzapple projects that his StarRotor engine, which is being developed by a company of the same name, could deliver efficiencies of 49–55% applied in a passenger car—about 2.5 to 3 times more efficient than a conventioanl gasoline engine.
The StarRotor engine. In the classic Brayton-cycle engine, ambient air is pressurized in a compressor, passed to a mixing chamber where fuel is added, and then ignited in an expansion chamber. It then expands through a piston/cylinder.
|The Brayton cycle.|
As applied to gas turbines, the Brayton engine has a compressor, a burner and an expansion turbine. Ambient air is compressed and passed through a heat exchanger for pre-heating. The pre-heated charge goes to a combustor where fuel is ignited, and the hot compressed air then flows to an expander where the thermal energy is converted to shaft work. The hot exhaust gases from the expander are sent to the heat exchanger where they are cooled and then discharged.
Brayton cycle engines have a high power density (hence their use in jet aircraft), compared to the lower power density of Otto (spark ignition) and Diesel engines.
The major challenge in implementing Brayton cycle engines, according to an analysis done for the Defense Advanced Research Projects Agency by Holtzapple, is to find a means to process large volumes of air to achieve a desired power output.
Traditionally, this is accomplished using dynamic (i.e., axial or centrifugal) compressors and expanders. The devices, however, require very high speeds—e.g., 100,000 rpm for a 30kW unit—to develop the desired pressure and flow. They also operate efficiently at only one speed, and are affected by changes in air density.
The patented StarRotor Brayton cycle engine uses gerotors for both the compressor and expander. (A gerotor is a positive displacement pump mechanism that delivers a known, predetermined quantity of fluid in proportion to speed.)
The StarRotor compressor has an inner gerotor with n teeth and an outer gerotor with n + 1 teeth. As the gerotors rotate, the void that opens draws air in through the inlet port. As the rotation continues, the void closes and compresses the air. When the air is compressed enough, the compressed air exhausts through the outlet port.
Because the void opens n + 1 times per revolution of the outer gerotor, the gerotor compressor is able to process enormous volumes of gas in a very compact size. The expander operates similarly to the compressor, except in reverse.
|The StarRotor applied in a vehicle could yield efficiencies of 49 to 55% and fuel economy of 75 to 100 mpg, according to Holtzapple.|
The gerotor teeth must be dry—lubricants are not compatible with the high temperatures. To prevent wear and friction, there must be no physical contact between the teeth of the inner and outer gerotors. StarRotor employs an inexpensive surface treatment to minimize gas leakage through the small gap, and an external synchronization mechanism ensures proper motion of the inner and outer gerotors.
The StarRotor, according to Holtzapple, can offer power ranges from 50W to 50,000kW. Lower-power versions employ a single stage that compresses air from 1 to 6 atm. The medium-power engines employ a second stage that compresses air from 6 to 36 atm. The high-power engines employ a third stage that compresses air from 36 to 216 atm. The power density is improved by using small-diameter rotors that rotate rapidly.
|Energy Content of Fuels|
|MixAlco Blend 1||29.0||104,000|
|MixAlco Blend 2||26.5||95,000|
MixAlco. The MixAlco process converts biomass into organic chemicals and alcohols with a multi-stage process that includes lime pretreatment, non-sterile acidogenic digestion, product concentration, thermal conversion to ketones and their subsequent hydrogenation to create mixed alcohol end products.
We can use anything that biodegrades. If you put it outside and it rots, we can use it. So we can use trees, grass, manure, sewage sludge or garbage.—Mark Holtzapple (The Eagle)
The MixAlco process consumes about 90% of the raw material substrate, and the process recycles all of its water and primary reagents. It can be tuned to produce the chemicals most in demand at a given time.
|MixAlco Chemical flowchart. Click to enlarge.|
US Patent # 6,336,317: Quasi-isothermal Brayton cycle engine