Tag Archives: Efficient

A Better Solution?

While there has been much attention on light rail, the fact is that there are better alternatives that provide our communities with a better and more flexible infrastructure that can evolve to take advantage of new technology advances like autonomous vehicles, electric batteries, new business models and power distribution. By using asphalt roads, we can have a more flexible addition to our transit infrastructure that can be used by BRT, interlined with existing buses in congested areas, promote car pooling by using HOV (High Occupancy Vehicle) and eventually leverage that infrastructure with emerging autonomous vehicles … instead of building a ‘steel road’ with rails.

Bus Rapid Transit (BRT) has gained attention as a potentially cost-effective form of high-capacity transit. This is particularly the case in small to medium-size cities that do not have high enough densities or serious enough peak-period traffic congestion to justify fairly expensive fixed-guideway transit investments. — UC Berkeley Urban Densities and Transit: A Multi-dimensional Perspective

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What is Bus Rapid Transit?

Bus Rapid Transit (BRT) continues to expand globally, with over 400 BRT lines in 195 cities serving approximately 32.4 million people daily. BRT is a high-quality, high-capacity rapid transit system that improves upon traditional rail transit systems at a significantly lower cost (eg Chapel Hill Transit implementation along NS corridor is estimated to cost less than $15 million per  mile). Vehicles travel in dedicated lanes with traffic signal priority thereby avoiding competing traffic. Passengers walk to comfortable stations, pay their fares in the station, and board through multiple doors just like a train.

So this allows us to take advantage of all of the best attributes of LRT while providing additional flexibility of sharing with other wheel-based (not rail-based) systems and the ability to reconfigured routes to adjust to our changing population and commuting patterns. For example, allowing other buses (potentially autonomous in the future) to ‘interline’ within the dedicated guideway, and ‘platooning‘ automated vehicles within the same guideway. A sort of flexible smart vehicle HOV lane which can evolve as technology changes and adapt to changing traffic patterns.

Interlining refers to the ability of local bus routes, including feeder bus services to utilize the BRT running way for a portion of their trip. It is an accepted practice for BRT systems and allows more transit users to benefit from the guideway investment.

And with the federal government expected to cover 80% of the BRT costs, would allow us to stretch our local taxes even further. In addition, BRT guideways could provide additional utility for emergency response vehicles (improving response times) and could be used for evacuation route due to natural disaster, etc

Indy-Connect_Explaining-BRT-1024x654Graphic courtesy of Indy Connect

Coming soon to Chapel Hill and Wake County!

BRT is coming to the Chapel Hill as part of the North-South Corridor that will connect Southern Village with UNC and continue north along MLK. The study area runs from the Eubanks Road Park & Ride lot (a northern terminus) and the popular Southern Village (the southern terminus) and points in between. The NS BRT with a projected cost of $125 MILLION (8.2 miles @ $15 MILLION per mile) to start service in 2020 with annual operating cost of $3.4 MILLION.

So with BRT, Chapel Hill will get mass public transit sooner (a decade earlier than DOLRT) at fraction of the cost (11% of the cost per mile to build and 12% of the operating cost) with lower local funding requirement due to higher federal grants!  In fact, passengers could ride BRT for ‘fare-free’ and it would still be cheaper (for riders and taxpayers) than DOLRT to operate.

For the same amount of money, we could build 166 miles of BRT (vs 17 miles of DOLRT). Now that would be mass public transit!.

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In addition to Chapel Hill, Wake County is planning to implement cost-effective BRT for 20 miles at $347 million ($17M per mile). Financially, Bus Rapid Transit is a better ‘price performer’ and maximizes our return on tax dollar investment over Light Rail. As a matter of fact, for the estimated $400 million in local taxes set aside for DOLRT, we could fund the NSCBRT and an equivalent Durham Orange BRT and still have funds left over! All from changing the technology to use rubber wheels rather than steel wheels.

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A study by the Institute of Transportation and Development Planning that analyzed 21 transit projects in 13 cities across the United States and Canada. Based on their in depth research and analysis, they concluded that there is no case in the United States where Light Rail should be favored over Bus Rapid Transit. Any perceived advantages of LRT over BRT are primarily aesthetic and political rather than technical.

Long term potential of BRT versus LRT?

One of the major advantages of BRT over proposed DOLRT is that it is much more flexible and can be integrated into our overall transportation infrastructure. Think about all of the rail lines and how much space they consume (50′ right of way for LRT vs 12′ for a highway lane or roughly equivalent to 4 lanes), and the majority of the time they are not being used. Sitting there, waiting for the next train to arrive. And only trains can use it, and cannot be shared with other vehicles. LRT also requires additional constraints (and expense) with limits on how steep the steel roads can be and require (exclusive) “overhead” electrification infrastructure to distribute the electricity (and losing 7% in distribution along the guideways) along the 17 miles.

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BRT on the other hand uses roadways that can be shared now! For example, with a dedicated BRT lane, other buses can ‘hop on and off’ in short segments to bypass areas with traffic congestion. As new technologies continue to evolve, BRT and it’s infrastructure can potentially take advantage of these disruptive innovations. For example, advances in wireless / induction charging, solar roads, batteries, photovoltaics, thermoelectrics, autonomous vehicles, and many other breakthroughs. Investments in BRT infrastructure would provide flexibility and ‘future-proof’ our transit investments.

Wireless (induction) charging is already powering buses in Texas, Utah, Berlin, Mannheim (Germany) and London. eBuses in Torino, Italy have used induction charging since 2003, Utrecht (Netherlands) since 2010, Gumi (South Korea) since 2013. And France is installing 1000 km of solar roads over the next 5 years.

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SOURCE: The UK Is Getting All Charged Up Over ULEV Roadways

Automated buses

The self-steering bus developed by California Partners for Advanced Transit and Highways follows magnetic strips embedded in the road, although drivers still handle acceleration and braking and can take full control of the bus at any time. The technology could make life better for passengers by increasing efficiency, and could cut the cost of rapid transit systems.

“The magnetic guidance system developed at UC Berkeley can both improve safety and provide a smoother ride for our passengers,” says Chris Peeples, president of the board of directors for the Bay Area transit agency AC Transit. “The system has the potential to make bus rapid-transit routes — particularly those that involve bus-only lanes — as efficient as light rail lines, which in turn will make buses more efficient in getting people out of their cars.” — Look Ma, No Hands! Automated Bus Steers Itself

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More Efficient?

Advocates portray the No Build option as perpetuating unsustainable urban sprawl, and that the only option is to build a light rail system. Let’s look at this a little closer.

The latest revised DOLRT  projects 27,000 daily boardings (with NCCU extension in 2040) during 18.5 hours of daily operation across the 17.7 mile circuit (at a cost of $2.5 BILLION or $141 million per mile) to serve an average 730 passengers per hour (on each track). Running 150 train trips per day will result in an average ‘load factor’ of 10 passengers per vehicle mile traveled; or utilize 2% of the 500 passenger capacity heralded by GoTriangle. So for every one train that travels at the cited 500 passenger capacity, there will be ~50 trains running empty. Low capacity utilization is not  environmentally or economically sound.

While advocates will argue that LRT has higher ‘capacity’, it will not necessarily mean that it has higher ‘usage.’ We should not confuse capacity with usage.

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So how does that compare to the much hated highway? Well, not so well. A typical highways can accommodate 2,200 vehicles per lane per hour (human driven), utilizing about 5% of roadway capacity. And as autonomous vehicles become pervasive, this capacity will increase significantly, as the vehicles will be able to ‘platoon’ at much closer proximity thereby dramatically increasing the capacity of our existing roadway infrastructure. By using BRT, we will be able to organically add this capacity; whereas with LRT relying on steel rails, we will not, as it will be dedicated to only for the train and we will not be able to share with other autonomous vehicles.

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Generally, one-half or more of the light rail riders formerly rode bus services that were replaced by the rail service. The new ridership attracted to light rail from freeways is in fact quite small compared to the carrying capacity of a single freeway lane. The average freeway lane in US metropolitan areas that have built new light rail systems (since 1980) carries four times as many people per mile as light rail. Even signalized surface streets average twice as many people per mile as light rail. — Breach of Faith: Light Rail and Smart Growth in Charlotte

The mean travel time to work according to the 2014 US Census is 21.5 minutes (Durham County) and 22.0 minutes (Chapel Hill), yet the proposed DOLRT will take 46 minutes (+10 minutes at terminus) . Now include the waiting time for the next train, the time to get to/from the station (via Park&Ride, Kiss&Ride, bicycle, walking, or bus transfer), it will even be LONGER. So how is this faster than the automobile that it is supposed to replace?

A Different Future?

“The future ain’t what it used to be.” Yogi Berra


We are in the midst of a massive revolution that will dramatically transform ground transportation. It is anticipated that autonomous vehicles (or driver-less cars) will be commercially available by 2020, if not sooner. By the time DOLRT is completed, technological advances in personal transportation alternatives will render DOLRT obsolete.

A wave of new transportation technology is coming to Columbus after the city won the federal Smart City Challenge. The grant money will usher in driverless cars but could end the idea of rail as a mass-transit option. “The City of Columbus plans to leap-frog fixed rail” by using new modes of transportation, Columbus says in the U.S. Department of Transportation application. The city last month won a $40 million grant from the U.S. Department of Transportation, besting cities like San Francisco and Portland, Oregon. They already have rail options and still struggle with traffic congestion. Those cities are also larger and attract far more visitors to their cores. The fact that Columbus is without rail might actually have helped its case in the smart-city competition, as it is the test case for new transportation methods that could scale to similar cities.  Columbus is the biggest city in the U.S. to not offer rail service – something like light rail, streetcars, monorail – as a mass transportation option. The city’s application said its bus-based mass transit system, operated by the Central Ohio Transit Authority, can “demonstrate emerging mobility solutions at a lower cost and with greater flexibility than a fixed-rail infrastructure.” — Columbus will ‘leap-frog’ light rail as transit option after Smart City Challenge win

According to Philippe Crist, an economist with the Organization for Economic Co-operation and Development (OECD) “Fleets of shared, self-driving vehicles could indeed remove nine out of every ten vehicles on city streets, eliminating the need for all on-street parking and 80% of off-street parking, according to a recent study by the group.”Urban Transit’s Uncertain Future

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The rise of a “taxibot” may further reduce the need for car ownership and enable the sharing of vehicles that make shared, self-driving vehicles possible. According to Emilio Frazzoli, head of Future Urban Mobility for the Singapore-MIT Alliance for Research and Technology  “You couldn’t have imagined this ten years ago when people didn’t have smart phones and mobile computing was not available. Now you have this ability to connect and book a car. You see it with Uber and the proliferation of taxi booking apps or public transportation schedule routing apps, and this is at the same time you have autonomous vehicle technology that is evolving. You can marry the two.” — Urban Transit’s Uncertain Future

LIDAR on chip.001.jpegIf you doubt the accelerating adoption of new technology, it is worth to pause for a moment and consider that the iPhone was introduced in June 2007 and now is a ubiquitous device that has fundamentally transformed entire industries. The mass adoption of new technologies continues to accelerate. One recent estimate suggests that the typical luxury sedan now contains over 100 MB of binary code spread across 50–70 independent computers.

An analysis of the history of technology shows that technological change is exponential, contrary to the common-sense “intuitive linear” view. So we won’t experience 100 years of progress in the 21st century — it will be more like 20,000 years of progress (at today’s rate). — The Law of Accelerating Returns

Imagine a company like Uber or Lyft using self-driving cars and a mobile app to provide point-to-point transportation. So instead of your going to the transportation system (DOLRT station), the transportation system (Uber) comes to you! Just use your mobile app, select your destination, schedule your pick-up time and you will be taken from your front door directly (or even carpooling) to your destination. This would help eliminate the waste of unnecessary side trips, parking, platooned with coordinated traffic signals.

Uber and Gilt are selling passes for unlimited uberPOOL rides in New York City. “The deal is being called a “commute card” and can only be used Monday through Friday during commuting hours (7-10am and 5-8pm) in Manhattan. These are the same hours during which Uber offers $5 flat rate uberPOOL rides in NYC. As a refresher, uberPOOL is Uber’s carpool product where the company matches you with riders headed the same direction … this deal means commuting in an uberPOOL is cheaper than taking the subway.”

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Uber and Lyft are looking beyond competition with traditional taxi services. They may be creating the first practical, affordable personal rapid transit (PRT) systems that will compete with buses. In 2014, Uber launched UberPool, enabling multiple parties to share a ride along similar routes. The following year, the company announced uberCOMMUTE in China, which they described as ” carpooling at the press of a button.” In the U.S., it’s being tested in Chicago. Then, in December, Uber launched uberHOP in Seattle, which operates along pre-selected commuters routes.

Virtually all mass transit systems are publicly subsidized. Farebox revenues rarely cover more than 50 percent of expenses, which are labor and capital-intensive. In Pinellas Park, Florida—a Tampa suburb—has just replaced two bus lines with Uber service, subsidized to the tune of $3 per ride. It’s cheaper than running the buses. The Pinellas Suncoast Transit Authority budgeted $40,000 a year. Running the two bus lines cost four times as much. — Uber and Lyft Revolutionize Public Transit

A recent study by the Boston Consulting Group found the cost of conveying one passenger by an autonomous vehicle would be 35% less than by conventional taxi at the average taxi occupancy rate of 1.2 passengers. Increase an autonomous vehicle’s rate of occupancy to just two passengers and the cost per passenger becomes competitive with mass transit.Urban Transit’s Uncertain Future

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“… private companies like Uber, which recently began test-driving its own autonomous vehicle, could drive down the cost of shared transport to such a point that car ownership wouldn’t be worth it.” — Urban Transit’s Uncertain Future

In addition, autonomous vehicles will greatly enhance mobility for transit dependent populations that may be disabled, too young or too old. For example, in the US there are approximately 36 million people with disabilities. Given the mobility and autonomy of this new technology, this will improve utilization of assets like vehicles, roadways and parking lots to further reduce the cost of these services by providing better efficiency.

U.S. transportation chief visits Google to unveil 30-year plan
“We’ve got to look at our own regulatory framework … to make sure we’re being as nimble and flexible and adaptive as we can be. … That’s what the future is demanding,” Foxx said. Foxx and Schmidt took a quick ride in the tiny electric-powered pod that dropped them off at an entrance to the corporate campus. It then drove away on its own. “This is awesome, this is cool,” Foxx remarked as Schmidt and Chris Urmson, the head of Google’s self-driving car project, showed him how it worked.

Autonomous vehicles will be a disruptive innovation with major implications for society. requiring policy makers to address many unresolved questions about their effects. One fundamental question is about their effect on travel behavior. It will be easier to share cars and that this will thus discourage outright ownership and decrease total usage, and make cars more efficient forms of transportation in relation to the present situation. Autonomous vehicles may reduce public transit travel demand, leading to reduced service.

bosch-autonomous-car-technology_100417251_hThink that’s unlikely? Many companies are investing heavily in this area and it will have a massive impact on how we move people (and things). Several companies have already announced that they will have partially autonomous vehicles (Level 3) ready in the next 5-6 years including Audi. Baidu, BMW, Ford, Google, LeTV, Mercedes, Nissan, Tesla, Uber

The avionics system in the F-22 Raptor, the current U.S. Air Force frontline jet fighter, consists of about 1.7 million lines of software code. The F-35 Joint Strike Fighter, scheduled to become operational in 2010, will require about 5.7 million lines of code to operate its onboard systems. And Boeing’s new 787 Dreamliner, scheduled to be delivered to customers in 2010, requires about 6.5 million lines of software code to operate its avionics and onboard support systems.

These are impressive amounts of software, yet if you bought a premium-class automobile recently, ”it probably contains close to 100 million lines of software code,” says Manfred Broy, a professor of informatics at Technical University, Munich, and a leading expert on software in cars. All that software executes on 70 to 100 microprocessor-based electronic control units (ECUs) networked throughout the body of your car. — This Car Runs on Code

Disruptive innovation in terms of low-cost and high-quality can shape the market even before the launch. One such example is the technology developed by a 19-year-old Romanian high-school student, Ionut Budisteanu, who created a camera and radar system for autonomous cars that costs a fraction (10%) of the cost for the existing solutions. Or Edgar Sarmiento, a 24-year-old from Columbia, who designed a self-driving minibus and built it in weeks with Local Motors. Or recent advances by MIT which has reduced the large and expensive LIDAR to lidar-on-a-chip system that is smaller than a dime, has no moving parts, and could be mass produced at a very low cost to be used in self-driving cars, drones, and robots.

 

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What is an Autonomous Vehicle?

In the United States, the National Highway Traffic Safety Administration (NHTSA) has proposed a formal classification system:

  • Level 0: The driver completely controls the vehicle at all times.
  • Level 1: Individual vehicle controls are automated, such as electronic stability control or automatic braking.
  • Level 2: At least two controls can be automated in unison, such as adaptive cruise control in combination with lane keeping. Many of these features are available in cars today.
  • Level 3: The driver can fully cede control of all safety-critical functions in certain conditions. The car senses when conditions require the driver to retake control and provides a “sufficiently comfortable transition time” for the driver to do so.
  • Level 4: The vehicle performs all safety-critical functions for the entire trip, with the driver not expected to control the vehicle at any time. As this vehicle would control all functions from start to stop, including all parking functions, it could include unoccupied cars.

An increase in the use of autonomous cars would:

  • Increased roadway capacity and reduced traffic congestion due to reduced need for safety gaps and the ability to better manage traffic flow.
  • Reduce total number of cars by increased car-sharing, since an autonomous car can drop off a passenger at one location and go to a different location to pick up another. Also see Uber perpetual rides.
  • Higher speed limit for autonomous cars.
  • Greater efficiency with coordinate platooning using vehicle-to-vehicle and vehicle to infrastructure communications allowing for drafting, better mileage efficiency, faster transit times and coordinated traffic signaling.
  • Time-shifting freight traffic to off-peak hours, reducing congestion during peak travel times and increasing highway capacity.
  • Alleviation of parking scarcity, as cars could drop off passengers, park far away where space is not scarce, and return as needed to pick up passengers.
  • Reduction of physical space required for vehicle parking.
  • Elimination of redundant passengers – the robotic car could drive unoccupied to wherever it is required, such as to pick up passengers or to go in for maintenance. This would be especially relevant to trucks, taxis and car-sharing services.
  • Fewer traffic collisions, since unlike a human driver with limited situational awareness an autonomous car can continuously monitor a broad range of sensors (e.g. visible and infrared light, acoustic incl. ultrasound) both passive and active (LIDAR, RADAR) with a 360° field of view and thus more quickly determine a safe reaction to a potential hazard, and initiate the reaction faster than a human driver.
  • Avoid traffic collisions caused by human driver errors such as tail gating, rubbernecking and other forms of distracted or aggressive driving.
  • Relief of vehicle occupants from driving and navigation chores.
  • Removal of constraints on occupants’ state – in an autonomous car, it would not matter if the occupants were minors, elderly, disabled, unlicensed, blind, distracted, intoxicated, or otherwise impaired.
  • Reduction in the need for traffic police and premium on vehicle insurance.
  • Reduction of physical road signage – autonomous cars could receive necessary communication electronically (although physical signs may still be required for any human drivers).
  • Smoother ride.
  • Reduction in car theft, due to the vehicle’s increased awareness.
  • Removal of the steering wheel and remaining driver interface saves cabin space and allows a cabin design where no occupant needs to sit in a forward facing position

Individual vehicles may also benefit from information obtained from other vehicles in the vicinity, especially information relating to traffic congestion and safety hazards. Vehicular communication systems use vehicles and roadside units as the communicating nodes in a peer-to-peer network, providing each other with information. As a cooperative approach, vehicular communication systems can allow all cooperating vehicles to be more effective and increase efficiency of our existing roadway infrastructure thereby dramatically reducing traffic congestion. According to a 2010 study by the National Highway Traffic Safety Administration, vehicular communication systems could help avoid up to 79% of all traffic accidents.

In 2012, computer scientists at the University of Texas in Austin began developing smart intersections designed for autonomous cars. The intersections will have no traffic lights and no stop signs, instead using computer programs that will communicate directly with each car on the road.

Congestion and traffic operations can be reduced using autonomous vehicle through the use of sensors that can sense traffic flows by monitoring vehicle braking and acceleration through V2V monitoring. V2I monitoring can also be used to improve flow and safety in intersections and high-problem areas. These systems will utilize information from other vehicles, smart traffic systems and other forms of smart infrastructure, allowing for a much higher throughput of traffic and further reducing the risk of accidents through the use of predictive trajectory modeling.

 

Environmentally Friendly?

While many environmentalists quickly point out the adverse impact of the automobile — they quickly gloss over the environmental impact of near-empty light rail trains. The environmental impact of light rail, as a system, is considerably worse. The automobile takes passengers directly point-to-point (from origin to destination), but light rail requires supplemental trips to/from the station, whether via park-and-ride, kiss-and-ride, or bus.

Many environmentalists support rail-based transit for environmental reasons, but to date only BRT projects have been certified as greenhouse gas-reduction projects by the Clean Development Mechanism defined in the Kyoto Protocol (see Bogotá and Mexico City).  Additionally, the volume of vehicle-specific emissions that LRT and electric trolley bus systems produce depends on how their electric power is generated. If the source is coal-fired power plants, then the system may actually produce more CO2 than normal diesel vehicles do, even though people are exposed to fewer emissions on the street. Buses are major producers of particulate emissions unless they use low-sulfur fuels, have particulate traps and clean engines, or run on some source of fuel that is an alternative to diesel.

Compared to rail systems, BRT systems also tend to be less intensive users of concrete and steel. Producing steel and concrete and building underground or elevated concrete structures generates a large amount of CO2. Many heavy-rail metro projects cannot reduce enough operations-related carbon emissions during their first twenty years to compensate for their construction-related CO2 emissions. Surface LRT generates less construction-related CO2 but still tends to generate more than a BRT project does. — ITDP study, More Development For Your Transit Dollar

Using the overly optimistic 27,000 daily boardings projection (revised with NCCU extension in 2040) running 150 train trips per day across the end-to-end 17.7 mile line will result in an average ‘load factor’ of 10 passengers per vehicle mile traveled; or utilize 2% of the 500 passenger capacity heralded by GoTriangle. So for every one train that travels at the cited 500 passenger capacity, there will be ~50 trains running empty. Low capacity utilization is not  environmentally or economically sound.

From an energy intensity perspective, this low utilization has a devastating impact on DOLRT energy efficiency. With an average of 10 passengers per mile results in 6327 BTU per DOLRT passenger mile (63265 BTU per vehicle mile / 10 passengers per mile) compared to 3144 BTU for car travel or 4071 BTU for bus transit. So per passenger mile, DOLRT uses over twice the amount of energy of an average car!

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SOURCE: US Department of Energy, Oak Ridge National Laboratory – Transportation Energy Data Book, Edition 34, page 2-19, Table 2.14

Due to the limited coverage of light rail stations, light rail requires altered bus routes to “feed the beast”. These feeders add cost, consume more energy, increase travel distance and increase travel times, while compounding the traffic congestion they are supposedly trying to alleviate. The light rail system is forced to provide an entire, high-capacity vehicle even when there are only a few riders.

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The inconvenient truth is that not a single light rail in the US carries as many passengers as a single highway lane. The myriad of alternatives, like walking, bicycling, carpooling, van-pooling, congestion pricing, telecommuting, flexible working hours, parking reform, pricing strategies to improve bus utilization, etc — largely ignored while the money and attention is consumed by light rail.

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The proposed Durham-Orange Light Rail train has NO new renewable energy requirement and electricity sourced from Duke Energy which has been repeatedly cited for environmental transgressions. Duke Energy generates electricity primarily with nuclear, gas (sourced from ‘fracking’) and coal power plants. The Political Economy Research Institute ranks Duke Energy 13th among corporations emitting airborne pollutants in the United States. The ranking is based on the quantity (80 million pounds in 2005) and toxicity of the emissions. When the high energy costs and carbon emissions during construction are counted, the light-rail line is far “browner” than autos and highways.

Forgetting greenhouse effects during construction?

Neglecting to take into account the emissions associated with constructing buildings like train stations and laying the tracks may make train travel appear far more environmentally friendly than it actually is, the authors found.

“Most current decision-making relies on analysis at the tailpipe, ignoring vehicle production, infrastructure provision, and fuel production required for support,” wrote the authors. “We find that total life-cycle energy inputs and greenhouse gas emissions contribute an additional 63 percent for on road, 155 percent for rail, and 31 percent for air systems,” relative to those vehicles’ tailpipe emissions. — How Green is Rail Travel?

Cement manufacturing releases CO2 in the atmosphere both directly when calcium carbonate is heated, producing lime and carbon dioxide, and also indirectly through the use of energy if its production involves the emission of CO2.The cement industry produces about 5% of global man-made CO2 emissions, of which 50% is from the chemical process, and 40% from burning fuel. The amount of CO2 emitted by the cement industry is nearly 900 kg of CO2 for every 1000 kg of cement produced. — Cement wiki