AdBlue

AdBlue is the registered trademark for AUS32 (Aqueous Urea Solution 32.5%) and is used in a process called selective catalytic reduction (SCR) to reduce emissions of oxides of nitrogen from the exhaust of diesel engined motor vehicles. As the name AUS32 would suggest, it is a 32.5% solution of high-purity urea in demineralised water that is clear, non-toxic and is safe to handle. However, it can be corrosive for some metals, and must be stored and transported using the correct materials. The AdBlue trademark is currently held by the German Association of the Automobile Industry (VDA), who ensure quality standards are maintained in accordance with ISO 22241 specifications.

AdBlue is carried onboard SCR-equipped vehicles in specially designed tanks, and is dosed into the SCR system at a rate equivalent to 3–5% of diesel consumption. This low dosing rate ensures long refill periods and minimises the tank's impact on chassis space. On-highway SCR systems are currently in use throughout Europe, in Japan, Australia, Hong Kong, Taiwan, Korea, New Zealand and Singapore. The United States Environmental Protection Agency‎'s (US EPA) 2010 legislation will limit NOx to levels that will require North American trucks to be equipped with SCR post-2010. The current generic name in North America for AUS32 is diesel exhaust fluid (DEF). Some trucking industry OEMs have already developed branded SCR solutions, such as Daimler's BlueTec.

All European truck manufacturers currently offer SCR equipped models, and the future Euro6 emission standard is set to reinforce the demand for this technology. SCR systems are sensitive to potential chemical impurities in the urea solution, therefore, it is essential to maintain high standards of AdBlue quality according to the ISO 22241 standard.

The use of SCR technology in Europe made it necessary to develop an AdBlue supply infrastructure. AdBlue is available from thousands of service stations, this locator finder

is updated monthly with new Retail sites selling AdBlue. It can also be purchased in canisters of 5 or 10 litres (1.1 or 2.2 imp gal; 1.3 or 2.6 USgal) at service stations. Larger quantities of AdBlue can be delivered in, for example, 208 litres (46 imp gal; 55 US gal) drums, 1,000 litres (220 imp gal; 260 US gal) Intermediate Bulk Containers (IBCs), and bulk.

From http://en.wikipedia.org/

Vehicle inspection in the United States

In the United States, vehicle safety inspection is goverened by each state individually. 18 states have a periodic (annual or biannual) safety inspection program, while Maryland requires an inspection prior to registration or transfer of ownership only.

Under the Clean Air Act (1990), states are required to implement vehicle emission inspection programs in metropolitan areas whose air quality does not meet federal standards. The specifics of those programs vary from state to state. Some states, including Kentucky and Minnesota, have discontinued their testing programs in recent years with approval from the federal government.

In most states, such inspections are done at state-operated garages, usually near the local DMV office. Pennsylvania is a notable exception, instead opting to have privately-owned garages doing inspections with approval from PennDOT. The flip side to this though is that some independently-run garages will do what is commonly known in Pennsylvania as a "lick-'em-and-stick-'em", which simply has the person pay the inspection fee and has the sticker replaced without actually checking the vehicle. This is illegal in Pennsylvania, which among other penalties could lead to a fine for the garage and a revocation of their inspection privileges. Other independently-run garages as well as chains like Pep Boys, Midas, and car dealerships are more stringent and follow PennDOT guidelines for inspections.

States and Federal Districts with periodic (e.g., annual) vehicle safety inspections

* Delaware (every year or every two years; brand new cars are exempt for the first four years provided the car remains with the same owner. Older cars registered as antiques do not require emissions testing.)
* District of Columbia (every two years; the requirement for safety inspection for private cars will end October 1, 2009)
* Hawaii (every year, except brand new vehicles receive an inspection valid for two years, emergency vehicles, school vehicles, rental cars, vehicles used in public transportation, and other, every six months)
* Louisiana (every year; emission test in the Baton Rouge metropolitan area parishes of Ascension, East Baton Rouge, Iberville, Livingtston and West Baton Rouge)
* Maine (every year; emission test in Cumberland County)
* Massachusetts (safety inspection and emissions testing annually). In 2008 the tailpipe test for 1995 model year and older vehicles was discontinued, vehicles without OBD-II systems receive a visual check of exhaust components
* Mississippi (safety inspection every year)
* Missouri (Odd numbered model year renews in odd numbered year, even model year renews in even year, except new vehicles not previously titled which are exempt during the model year and the year following, or vehicles displaying historical plates, which are completely exempt.; emissions testing in St. Louis city, St. Louis County, St. Charles County, Franklin County, and Jefferson County)
* New Hampshire (annually, emissions testing for model year 1996 and newer vehicles))
* New Jersey (safety and emissions testing every two years, brand new cars are exempt for the first four years. Effective 2010, the new car four-year exemption will transfer to the next owner if sold before the end of the four years . Older cars registered as antiques do not require emissions testing. Diesel cars under 10000 lb are also exempt.
* New York (annual safety and emissions). Model year 1996 and newer vehicles are subject to an OBD-II emissions inspection while older cars receive a visual check of exhaust components. Vehicles registered in the five boroughs of New York City as well as Long Island, Westchester County and Rockland County require a tailpipe smog-test if they are not OBD II equipped. All OBD II vehicles in those areas (1996 model year or newer) require only the OBD II test. And any vehicle 26 model years old or more does not require an emissions check of any sort. Newly registered vehicles from another state with a current inspection sticker are exempt until the out-of-state sticker expires or for one year, whichever is sooner.
* North Carolina (every year; emissions inspections in 48 of 100 counties (1996-newer, except new cars), exempting diesels and cars 35 years or older. Starting Nov 1, 2008 there won't be an inspection decal issued upon passing. )
* Pennsylvania every year for most vehicles; every six months for tractor-trailers, school vehicles (including school buses and school vans), motor coaches, mass transit buses, ambulances, fire department trucks, etc.; emissions inspections every year in 25 of 67 counties (stricter in the Pittsburgh and Philadelphia metro areas) (no emission inspection for diesel vehicles))annual inspection, emission, and semi-annual inspection stickers are color-coded, which tells which month of the year they expire. This makes it easier for police to be aware of expired stickers.
* Rhode Island (safety and emission inspection every two years)
* Texas (every year; emission test in the largest urban areas - Houston Metro, Dallas Metroplex, Austin, San Antonio, and El Paso)
* Utah (every two years for the first eight years, then every year)
* Vermont (every year)
* Virginia (every year; emission inspection every two years in urban and suburban jurisdictions in Northern Virginia)
* West Virginia (every year - safety)

States with safety inspection only required prior to sale or transfer

* Alabama
* Maryland (emission inspection required every two years in all counties)(not required in every county. The VEIP testing network consists of 18 centralized inspection stations located in 13 counties and Baltimore City)

States which only require federally mandated emissions inspections

* Arizona (Phoenix and Tucson metro areas only) annually, depending on age and type of vehicle)
* California (for most ZIP codes, every two years for all vehicles made after 1975 which are more than six years old)
* Colorado (in some localities, every year or two, depending on age and type of vehicle)
* Connecticut (every two years)
* Georgia (metropolitan Atlanta area only, every year, most recent three model year cars are exempt)
* Illinois every two years after the vehicle is four years old (Chicagoland and eastern suburbs of St. Louis, Missouri)
* Indiana (Lake and Porter counties only, every two years)
* New Mexico (Albuquerque metro area)
* Nevada (Clark County and Washoe County areas)
* Ohio (Cuyahoga, Geauga, Lake, Lorain, Medina, Portage, and Summit counties only) cars that are four years old or less do not have tested, after that period they have to tested. Testing is based on a odd-even year system. If a car was bought in 2000, it wont tested until 2010, if a car was purchased in 2003, then it will need to be tested in 2009. Franklin County (Columbus) and Hamilton County (Cincinnati) will also have be under emission testing effective in 2010. Ohio does not charge a fee for emission testing, due to Ohio's tobacco settlement.
* Oregon (Portland and Medford metro areas only)
* Tennessee in conjunction with annual registration renewal (Davidson, Hamilton, Rutherford, Sumner, Williamson or Wilson counties and city of Memphis only)
* Washington (urban areas of Clark, King, Pierce, Snohomish and Spokane counties)
* Wisconsin (Kenosha, Milwaukee, Ozaukee, Racine, Sheboygan, Washington and Waukesha; every two years)

States requiring an inspection only when bringing a vehicle from another State or jurisdiction

* Nebraska (all vehicles, ATVs, minibikes and trailers brought into Nebraska from Out-of-State)

States without safety or emissions inspections

* Alaska
* Arkansas
* Florida
* Idaho (Ada County has a county level program that requires testing)
* Iowa
* Kansas
* Kentucky
* Michigan
* Minnesota
* Montana
* North Dakota
* Oklahoma
* South Carolina
* South Dakota
* Wyoming

From http://en.wikipedia.org/

Indonesia Earthhour

change the world in one hour. Switch off the lights Saturday, 27 March 2010 at 20:30 to 21:30. You can see all information about Indonesia Earthhour at www.earthhour.wwf.or.id

From http://en.wikipedia.org/

Vehicle inspection

Vehicle inspection is a procedure mandated by national or subnational governments in many countries, in which a vehicle is inspected to ensure that it conforms to regulations governing safety, emissions, or both. Inspection can be required at various times, e.g., periodically or on transfer of title to a vehicle. If required periodically, it is often termed periodic motor vehicle inspection; typical intervals are every two years and every year.

In some jurisdictions, proof of inspection is required before a vehicle licence or license plate can be issued or renewed. In others, once a vehicle passes inspection, a decal is attached to the windshield, and police can enforce the inspection law by seeing whether the vehicle displays an up-to-date decal. In the case of a vehicle lacking a windshield (e.g., a trailer or motorcycle), the decal is typically attached to the vehicle body or license plate.

With regard to safety inspection, there is some controversy over whether it is a cost-effective way to improve road-traffic safety.

From http://en.wikipedia.org/

Supplementarity

The supplementarity principle, also referred to as the supplementary principle, is one of the main principles of the Kyoto Protocol. The concept is that internal abatement of emissions should take precedent before external participation in flexible mechanisms. These mechanisms include emissions trading, Clean Development Mechanism (CDM), and Joint Implementation (JI).

Emissions trading basically refers to the trading of emissions allowances (carbon credits) between one regulated entity and a less pollutive entity. This trading of permits results in a marginal economic disincentive to the buyer and a marginal economic incentive the abater.

CDM and JI are flexible mechanisms based on the concept of a carbon project. These projects reduce GHG voluntarily (outside the capped sectors) and therefore can be imported into the capped sector to aid in compliance.

The supplementarity principle is found in three articles of the Kyoto Protocol: article 6 and 17 with regards to trading, and article 12 with regards to the clean development mechanism.

Article 6.1 states that "The acquisition of emission reduction units shall be supplemental to domestic actions for the purposes of meeting commitments under Article 3". Article 17 states that "Any such trading shall be supplemental to domestic actions for the purpose of meeting quantified emission limitation and reduction commitments under that article". Article 12.3.b states that "Parties included in Annex I may use the certified emission reductions accruing from such project activities to contribute to compliance with part of their quantified emission limitation and reduction commitments under Article 3".

The actual meaning of the principle has been heavily argued since the signing of Kyoto Protocol in 1997. The COP/MOP is the body that represents the signers/ratifiers of the protocol and they have not been able to agree on a specific definition of the limit on use of flexible mechanisms. The original text has been interpreted to mean that anywhere from 3-50% of emissions could be offset by trading mechanisms. However, the only determination that has been thustly made is that the actual value of supplementarity should be decided at the country level.

In the United States RGGI (Regional Greenhouse Gas Initiative) has set a precedent in that it will initially allow only up to 3.3% compliance occur by means of offset projects (carbon projects). This value can increase to 5% and ultimately 10% if certain price thresholds are exceeded in the region.

From http://en.wikipedia.org/

Sandbag (non-profit organisation)

Sandbag is a non-profit campaign group designed to increase public awareness of emissions trading. The organisation was announced in 2008 by Bryony Worthington and was the first (and founding) member of The Guardian's Environment Network.

The Sandbag website centres on the European Union's Emission Trading Scheme and allows its members to campaign to reduce the number of permits in circulation and to purchase permits and cancel them. Large corporations (such as vehicle manufacturers) must obtain these permits from the EU if they need to emit greenhouse gases during production. The purchase of these permits by the public prevents their use by corporations. Worthington described her organisation as "a bit like burning money in front of someone so they can't spend it on something bad."

Worthington gave the first public talk on Sandbag (as well as emissions trading in general) at a geeKyoto meeting in London during May 2008.

From http://en.wikipedia.org/

Portable Emissions Measurement System

A Portable Emissions Measurement System (PEMS) is essentially a lightweight ‘laboratory’ that is used to test and/or assess mobile source emissions (i.e. cars, trucks, buses, construction equipment, generators, trains, cranes, etc.) for the purposes of compliance, regulation, or decision-making. Governmental entities like the United States Environmental Protection Agency (USEPA), the European Union, as various states and private sector entities have begun to utilize PEMS in order to reduce both the costs and time of mobile emissions decisions. Various state, federal, and international agencies began referring to this shorthand term in early 2000, and the nickname became part of industry parlance.

Background

Since the mid-1800’s, Dynamometers (or "dyno" for short) has been used to measure torque and rotational speed (rpm) from which power produced by an engine, motor or other rotating prime mover can then be calculated. A chassis dynamometer measures power from the engine through the wheels. The vehicle is parked on rollers which the car then turns and the output is measured. These dynos can be fixed or portable. Because of frictional and mechanical losses in the various drivetrain components, the measured horsepower is generally 15-20 percent less than the brake horsepower measured at the crankshaft or flywheel on an engine dynamometer . Historically though, dynamometer emission tests are very expensive, and have usually involved removing fleet vehicles from service for a long period of time. Also, the data derived from such testing is not representative of “real world” driving conditions, and cannot be deemed as quantifiable, especially due to the relatively low amount of repeatable tests at such a facility.

Introduction of PEMS

Portable systems began to be developed in the late 1990’s in order to better identify actual in-use performance of vehicles. PEMS are designed to measure emissions during the actual use of an internal-combustion engine vehicle or equipment in its regular daily operation, in a manner similar to operation on a chassis Dynamometer. This methodology and approach has been recognized by the USEPA

Many governmental entities (such as the USEPA and the United Nations Framework Convention on Climate Change or UNFCCC) have identified target mobile-source pollutants in various mobile standards as CO2, NOx, Particulate Matter (PM), Carbon Monoxide (CO), Hydrocarbons(HC), to ensure that emissions standards are being met. Further, these governing bodies have begun adopting in-use testing program for non-road diesel engines, as well as other types of internal combustion engines, and are requiring the use of PEMS testing. It is important to delineate the various classifications of the latest ‘transferable’ emissions testing equipment from PEMS equipment, in order to best understand the desire of portability in field-testing of emissions.

Defining Portability

An important step in the evaluation of a “Portable Emissions Measurement System” (PEMS) device is to define what a PEMS device is as well as to understand various classifications of ‘transferable vehicle testing equipment’:

Definition of the Term “Portable”

The word portable typically conveys an object that is “Carried or moved with ease, such as a light or small typewriter.”

Definition of the Term “Mobile”

The definition of mobile is essentially “…capable of moving or of being moved readily from place to place: a mobile organism; a mobile missile system.”

Definition of the Term “Instrumented”

Instrumented means to be “a device for recording, measuring, or controlling, especially such a device functioning as part of a control system.”

Therefore, the subtle difference between ‘portable’ and ‘mobile’ is that a portable system is a lightweight device able to be carried, whereas a mobile system can be readily moved, and ‘Instrumented’ means that the testing equipment has been incorporated into the host system. These distinctions are critical, especially considering additional guidelines from various US and International standards.

Definition determined by the National Institute for Occupational Safety and Health (NIOSH)

The National Institute for Occupational Safety and Health (NIOSH) defines these terms based on an equation known as the “NIOSH Lifting Equation” (http://www.cdc.gov/niosh/docs/94-110/pdfs/94-110-b.pdf

) and the “NIOSH Procedures for Analyzing Lifting Jobs (http://www.cdc.gov/niosh/docs/94-110/pdfs/94-110-c.pdf

). These clearly outline safety procedures and equipment. (these are also specified in the “Occupational Safety Hazard Act 29 CFR parts 1903, 1904, and 1910)

Safety Guidelines and Standards (the NIOSH Lifting Equation)

It is imperative to refer to existing federal standards and guidelines when determining a proper ergonomically safe and correct procedure. Not only is this important to ensure the safety of the worker(s), but also to ensure the reduction in potential future liability. Therefore, the revised NIOSH Lifting Equation is an excellent source of information to determine what a single worker should or shouldn’t perform.

Based upon the NIOSH lifting equation and assuming that this diagram is analgous to the lifting of a PEMS into the cab of a heavy duty truck the upper threshold of the total weight of a PEMS device typically should not exceed 45 lb (20 kg)., in order to be congruent with national and international safety standards. This not only allows for much more safe maneuverability and ease of use, but it also reduces the amount of workers required to safely perform such tasks.

Economic Advantage of PEMS Equipment

Because a PEMS unit is able to be carried easily by one person from jobsite to jobsite, and can be used without the requirement of ‘team lifting’, the required emissions testing projects are economically viable. Simply put, more testing can be done more quickly, by less workers, dramatically increasing the amount of testing done in a certain time period. This in turn, significantly reduces the ‘cost per test’, yet at the same time increases the overall accuracy required in a ‘real-world’ environment. Due to the fact that the law of large numbers will create a convergence of results, it means that repeatability, predictability, and accuracy are enhanced, while simultaneously reducing the overall cost of the testing.

On-road Emissions Patterns Identified by PEMS

Nearly all modern engines, when tested new and according to the accepted testing protocols in a laboratory, produce relatively low emissions well within the set standards. As all individual engines of the same series are supposed to be identical, only one or several engines of each series get tested. The tests have shown that:

1. The bulk of the total emissions can come from relatively short high-emissions episodes
2. Emissions characteristics can be different even among otherwise identical engines
3. Emissions outside of the bounds of the laboratory test procedures are often higher than under the operating and ambient conditions comparable to those during laboratory testing
4. Emissions deteriorate significantly over the useful life of the vehicles
5. There are large variances among the deterioration rates, with the high emissions rates often attributable to various mechanical malfunctions

These findings are consistent with published literature, and with the data from a myriad of subsequent studies. They are more applicable to spark-ignition engines and considerably less to diesels, but with the regulation-driven advances in diesel engine technology (comparable to the advances in spark-ignition engines since 1970’s) it can be expected that these findings are likely to be applicable to the new generation diesel engines. Since 2000, multiple entities have utilized PEMS data to measured in-use, on-road emissions on hundreds of diesel engines installed in school buses, transit buses, delivery trucks, plow trucks, over-the-road trucks, pickups, vans, forklifts, excavators, generators, loaders, compressors, locomotives, passenger ferries, and other on-road, off-road and non-road applications. All the previously listed findings were demonstrated; in addition, it was noticed that extended idling of engines can have a significant impact on the emissions during subsequent operation.

Also, PEMS testing identified several engine “anomalies” where fuel-specific NOx emissions were two to three times higher than expected during some modes of operation, suggesting deliberate alterations of the engine control unit (ECU) settings. Such data set can be readily used for developing emissions inventories, as well as to evaluate various improvements in engines, fuels, exhaust after-treatment and other areas. (Data collected on “conventional” fleets then serves as “baseline” data to which various improvements are compared.) This data set can also be examined for compliance with not-to-exceed (NTE) and in-use emissions standards, which are ‘US-based’ emission standards that require on-road testing.

PEMS Accuracy, Measurement Errors

The question often arises as to the target accuracy of PEMS. As PEMS are typically limited in size, weight and power consumption, it is often difficult for PEMS to offer the same accuracy and variety of species measured as is possible with top of the line laboratory instrumentation. For this reason, objections were raised against using PEMS for compliance verification.

On the other hand, fleet emissions deduced from laboratory measurements can be subject to significant inaccuracies if the selected engines and operating conditions were not representative of the fleet, or if deliberate anomalies (i.e., dual mapping of the ECU) were not demonstrated during laboratory testing.

The question of how accurate a monitoring system needs to be therefore cannot be objectively answered, neither can a monitoring system be easily designed, without first considering the intended application of the system and the errors associated with different approaches.

It is expected that a variety of on-board systems will be designed, ranging from suitcase-sized PEMS to instrumented trailers towed behind the tested truck. The benefits of each approach need to be considered in light of other sources of errors associated with emissions monitoring, notably vehicle-to-vehicle differences, and the emissions variability within the vehicle itself. In other words, one needs to consider the total of:

1. The difference between what is measured and what is actually emitted during a test
2. The difference between what is emitted during the test and what the vehicle emits during its everyday duties
3. The difference between the emissions characteristics of the tested vehicle and the overall emissions levels of the entire fleet.

For example, when evaluating a benefit of cleaner fuels on a fleet of city buses, one needs to compare taking a bus out of service, installing a laboratory-grade monitoring system, loading it with sandbags and driving it on a simulated route against testing several buses on their regular routes, with passengers on board, using a simpler (and possibly less accurate) monitoring system.

Additional PEMS Criteria

Another important aspect that needs to be evaluated is the safety of using PEMS on public roadways. Extensions of the tailpipe, lines and cables extending far beyond the vehicle sides, lead-acid batteries located in the passenger compartment of a bus, sharp objects, hot components accessible to bystanders, equipment blocking emergency exits or interfering with the driver, loose components likely to be caught on moving parts, and other potential hazards need to be examined. Also, any modifications to or disassembly of the tested vehicle (i.e., drilling into the exhaust, removing intake air system) need to be examined for their acceptance by both fleet managers and drivers, especially on passenger-carrying vehicles. The source of power for PEMS is a concern, as only a limited amount of power can be extracted from the vehicle electrical system. Sealed lead-acid batteries, fuel cells and generators have been used as external power sources, each with a potential significant hazard when driven on the road. A PEMS also has to be practical. Installation time and the expertise level required to perform installation and to operate the PEMS will have a significant impact on the cost of the test, and on the number of vehicles tested. Versatility (ability to test different vehicles) may be important if testing dissimilar engines or vehicles. Total size, weight and transportability of the PEMS needs to be considered when testing at different locations, including any consumables such as calibration gases. Any restrictions on transport of hazardous materials (I.E.Flame ionization detector (FID) fuel or calibration gases) need to be taken into the account. The ability of the test crew to repair PEMS in the field using locally available resources can also be essential when testing away from the base. Thus, PEMS evaluation protocol should be expanded. In addition to the laboratory comparison testing, which is a measure of how accurately PEMS measures when operated in a laboratory, the accuracy and repeatability of PEMS should also be examined on the road, possibly while driving along a well-defined, repeatable route, or while driving chassis dynamometer cycles on a test track.

PEMS Suitability to Application

Ultimately, it should be demonstrated to show that a PEMS is suitable to the desired application. If the ultimate goal is to verify the compliance with in-use emissions requirements, a fleet of vehicles with known characteristics – including engines with dual-mapping and otherwise non-compliant engines – should be made available for testing. It should be then up to the PEMS manufacturers to practically demonstrate how these non-compliant vehicles can be identified using their system.

Testing Volume and Safe Repeatability

In order to achieve the required amount of ‘testing volume’ needed to validate real-world testing, three points must be considered:

1. System accuracy
2. Federal and/or state health and safety guidelines and/or standards
3. Economic viability based on the first two points.

Once a particular portable emissions system has been identified and pronounced as accurate, the next step is to ensure that the worker(s) are properly protected from work hazards associated with the task(s) being performed in the use of the testing equipment. For example, typical functions for a worker may be to transport the equipment to the jobsite (i.e. car, truck, train, or plane), carry the equipment to the jobsite, and lift the equipment into position.

Advantages of PEMS

On-road vehicle emissions testing is very different from the laboratory testing, bringing both considerable benefits and challenges: As the testing can take place during the regular operation of the tested vehicles, a large number of vehicles can be tested within a relatively short period of time and at relatively low cost. Engines than cannot be easily tested otherwise (i.e., ferry boat propulsion engines) can be tested. True real-world emissions data can be obtained. The instruments have to be small, lightweight, withstand difficult environment, and must not pose a safety hazard. Emissions data is subject to considerable variances, as real-world conditions are often neither well defined nor repeatable, and significant variances in emissions can exist even among otherwise identical engines. On-road emissions testing therefore requires a different mindset than the traditional approach of testing in the laboratory and using models to predict real-world performance. In the absence of established methods, use of PEMS requires careful, thoughtful, broad approach. This should be considered when designing, evaluating and selecting PEMS for the desired application.

From http://en.wikipedia.org/

Onboard refueling vapor recovery

Onboard Refueling Vapor Recovery (ORVR) is a vehicle emission control system that captures fuel vapors from the vehicle gas tank during refueling. The gas tank and fill pipe are designed so that when refueling the vehicle, fuel vapors in the gas tank travel to an activated carbon packed canister, which adsorbs the vapor. When the engine is in operation, it draws the gasoline vapors into the engine intake manifold to be used as fuel. ORVR has been mandated on all passenger cars in the United States since 2000 by the United States Environmental Protection Agency‎. The use of onboard vapor recovery is intended to make vapor recovery at gas stations obsolete.

From http://en.wikipedia.org/

Not-To-Exceed (NTE)

The Not-To-Exceed (NTE) standard recently promulgated by the United States Environmental Protection Agency (EPA) ensures that heavy-duty engine emissions are controlled over the full range of speed and load combinations commonly experienced in use. NTE establishes an area (the “NTE zone”) under the torque curve of an engine where emissions must not exceed a specified value for any of the regulated pollutants. The NTE test procedure does not involve a specific driving cycle of any specific length (mileage or time). Rather it involves driving of any type that could occur within the bounds of the NTE control area, including operation under steady-state or transient conditions and under varying ambient conditions. Emissions are averaged over a minimum time of thirty seconds and then compared to the applicable NTE emission limits.

Creation of NTE

NTE standards were created by the EPA as a result of a consent decree between the EPA and several major diesel engine manufacturers. These manufacturers included Caterpillar, Cummins, Detroit Diesel, Mack, Mack's parent company Renault Vehicles Industriels, and Volvo Truck Corp. These manufacturers were accused of violating the Clean Air Act by installing devices that defeat emission controls. As part of the resulting consent decree settlement with the EPA, these manufacturers were assessed heavy fines and were subjected to new emissions standards which included NTE.

Current requirements to achieve engine operation in the "NTE Zone"

When all of the following conditions are simultaneously met for at least 30 seconds, and engine is considered to be operating in the NTE zone.

1. Engine speed must be greater than 15% above idle speed
2. Engine torque must be greater than or equal to 30% of maximum torque.
3. Engine power must be greater than or equal to 30% of maximum power.
4. Vehicle altitude must be less than or equal to 5,500 feet (1,700 m).
5. Ambient temperature must be less than or equal to 100 °F (38 °C) at sea level to 86°F at 5,500 feet (1,700 m).
6. Brake specific fuel consumption ([BSFC) must be less than or equal to 105% of the minimum BSFC if an engine is not coupled to a multi-speed manual or automatic transmission.
7. Engine operation must be outside of any manufacturer petitioned exclusion zone.
8. Engine operation must be outside of any NTE region in which a manufacturer states that less than 5% of in-use time will be spent.
9. For Exhaust gas recirculation (EGR) equipped engines, the intake manifold temperature must be greater than or equal to 86-100 degrees Fahrenheit, depending upon intake manifold pressure.
10. For EGR-equipped engines, the engine coolant temperature must be greater than or equal to 125-140 degrees Fahrenheit, depending on intake manifold pressure.
11. Engine after treatment systems’ temperature must be greater than or equal to 250 degrees Celsius.

Visual representations of NTE Zone



Example NTE Control Area for Heavy-Duty Diesel Engine With 100% Operational Engine Speed Less Than 2400 rpm



Example NTE Control Area for HeavyDuty Diesel Engine With 100% Operational Engine Speed Greater Than 2400 rpm

Description

The NTE test, as defined in CFR 86.1370-2007, establishes an area (NTE control area) under the torque curve of an engine where emissions must not exceed a specified emission cap for a given pollutant. The NTE cap is set at 1.25 times the FTP emission limit as described in the subsection above. For 2005 model year heavy-duty engines, the NTE emission cap for NMHC plus NOx is 1.25 times 2.5 grams per brake horsepower-hour, or 3.125 grams per brake horsepower-hour. The basic NTE control area for diesel engines has three basic boundaries on the engine’s torque and speed map. The first is the upper boundary that is represented by an engine’s maximum torque at a given speed. The second boundary is 30 percent of maximum torque. Only operation above this boundary is included in the NTE control area. The third boundary is determined based on the lowest engine speed at 50 percent of maximum power and highest engine speed at 70 percent of maximum power. This engine speed is considered the “15 percent operational engine speed”. The fourth boundary is 30% of maximum power

Controversy and deficiency regarding NTE standards

Controversy

A controversial issue is the applicability of the NTE limits to the real-world driving. In order for NTE standards to apply, the engine needs to remain within the NTE zone (limits include operation at a minimum of 30% of rated power) for at least 30 seconds. Concerns arose that performing this action could prove to be difficult, as each time the driver removes the foot from the accelerator pedal, or shifts gears on vehicles with manual transmission, the engine leaves the NTE zone.

In urban or suburban driving, this happens relatively often, to the point that NTE standards are applicable only a very small portion of the operation or, in some cases, not at all. The probability of the engine remaining within the NTE zone for over 30 seconds also decreases with the advent of high-power engines. For example, if the power required to maintain a motorcoach or an over-the-road truck at highway cruising speed is somewhere around 150 hp (110 kW), the probability that a 475 hp (354 kW) engine will consistently operate at loads above 30%, without “dips” to lower power levels, can be relatively small.

These concerns were confirmed by studies carried out by West Virginia University (WVU) under the Consent Decrees. WVU found that “remaining for 30 seconds within the NTE zone can be quite difficult. The resulting low NTE availability poses a problem as many measurements within the NTE area have to be rejected along with those from outside the NTE area. The question arises if in this way all real-life emissions are sufficiently ‘well reflected’ in the NTE test results”

A second issue of concern in the same vein is a case when an engine is compliant within the NTE zone, but exhibits elevated NOx at power levels just outside the NTE zone, or at idle. For reasons such as this the Working Group On Off Cycle Emissions is studying whether an extension of the NTE zone is rational as they ponder if there are spots on the engine map (outside of the NTE zone) that have a significant contribution in real life emissions. Their preliminary findings echo those of WVU as they found that the time of engine operation in the NTE zone is rather low.

EPA admitted deficiencies

According to the US EPA there are technical limitations of NTE under limited operating conditions which have caused the EPA to “carve-out” (see graphs above) certain portions of the NTE zone to allow for these deficiencies. Excerpts as follows:

“NTE zone was defined by a desire to have a homogeneous emissions limit. Carve-outs within that zone exclude certain areas of operation from NTE consideration or limit how much emissions from that operation can contribute to an NTE result, deficiencies allow temporary exceedences of the NTE standards due to technical limitations under limited operating conditions. The idea is not to hold the manufacturer responsible for NTE compliance during modes where the engine is not capable of operating or where it is not technically feasible to meet the NTE standards.”

Regarding the particulate matter “carve-out”

"PM-specific region is “carved out” of the NTE control area. The PM specific area of exclusion is generally in the area under the torque curve, where engine speeds are high and engine torque is low, and can vary in shape depending upon several speed-related criteria and calculations detailed in the regulations. Controlling PM in this range of operation presents fundamental technical challenges which we believe can not be overcome in the 2004 time frame. Specifically, the cylinder pressures created under these high speed and low load conditions are often insufficient to prevent lube oil from being ingested into the combustion chamber. High levels of PM emissions are the result. Furthermore, we do not believe that these engines spend a significant portion of their operating time in this limited speed and torque range"

Lawsuits and settlement

Lawsuits

In 2001, five separate lawsuits were filed against the US EPA by the Engine Manufacturers Association (EMA) and several individual trucking industry entities (such as International Truck and Engine Corporation). Each of those lawsuits challenged the legality and technological feasibility of certain engine emission control standards in EPA regulations now referred to as NTE requirements. In their challenge, EMA stated that to determine whether an engine meets a primary emission standard, engines are tested and assessed using a standardized 20-minute emissions laboratory test known as the Federal Test Procedure. The NTE, by contrast, has no specified test procedure and potentially could apply over an almost infinite number of test conditions. This, in the manufacturers’ view, made it virtually impossible to ensure total compliance with the NTE—since there is no real or practical way to test an engine under all conceivable conditions—and so made the NTE both unlawful (the CAA authorizes EPA to adopt engine standards AND accompanying test procedures) and technically infeasible.

Settlement

On June 3, 2003, the parties finalized a settlement of their disputes pertaining to the NTE standards. The parties agreed upon a detailed outline for a future regulation that would require a manufacturer-run heavy-duty in-use NTE testing (“HDIUT”) program for diesel-fueled engines and vehicles. One section of the outline stated:

“The NTE Threshold will be the NTE standard, including the margins built into the existing regulations, plus additional margin to account for in-use measurement accuracy. This additional margin shall be determined by the measurement processes and methodologies to be developed and approved by EPA/CARB/EMA. This margin will be structured to encourage instrument manufacturers to develop more and more accurate instruments in the future.”

HDIUT and Portable Emissions Measurement Systems (PEMS)

The ultimate objective of the new HDIUT program is to allow for a significant streamlining of engine certification if a truly robust in-use emissions testing program proves feasible and cost effective. Time-consuming and expensive laboratory assessments of engines could then give way to real-world, real-time emissions assessments that efficiently provides more relevant data.

Basically, the HDIUT is an industry agreed to manufacturer run, in-use, on-road testing program. It builds upon the original NTE standard. It is designed to focus on compliance in the real world, and relies on emissions testing, utilizing Portable Emissions Measurement Systems (PEMS) with NOx, HC, CO and PM being the pollutants to be measured. Measurement Accuracy Margins are being established to account for the emissions measurement variability associated with the PEMS in-use.

From http://en.wikipedia.org/