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Personal Rapid Transit (PRT) offers clean, quiet, responsive public transit with automated non-stop service available 24 hours a day.



PRT cab with 3 passengersAutomated Transit Networks (ATN), and the small-vehicle subset of Personal Rapid Transit (PRT), are emerging technologies that can help solve the related problems of congestion, dependence on foreign oil, and planetary climate change. ATN/PRT offers clean, quiet, responsive public transit with automated non-stop service available 24 hours a day. In addition to these service benefits, PRT costs far less to build and operate than other transit options – and is safer than walking and cycling on nearby busy streets.

Energy-efficient, non-stop electric-drive vehicles located above existing streets will breech barriers to other forms of transportation including traffic congestion, creeks, freeways and railroad lines. Intermodal by design, PRT will reduce CO2 emissions, resource usage, and wasted time.

This particular application of the technology – a circulator feeding the BART commuter rail station – could easily be expanded to serve the host city of Milpitas, CA or into a wide area of San José with hundreds of miles of guideway and hundreds of stations.

For brief video introductions to PRT technology and its potential, see

Is this proposal for a practice or a project?


What actions do you propose?

Cycling and walking are critical to a sustainable transportation future. In European cities renowned for their public transit, fewer than one in four trips involve transit. More than half, however, involve walking or biking. Here in Milpitas, like many cities across America, walking and biking is discouraged by physical barriers that prevent people from easily moving across town without a car. In Milpitas those barriers include creeks, freeways, railroad lines and Montague Expressway.

With the 2017 arrival of BART in Milpitas and the rapidly-growing population in the transit area around the station, the need for a bike/pedestrian crossing of Montague Expressway is rapidly growing. The City’s Transit Area Specific Plan, already indicates the need for 4 pedestrian/cyclist barrier crossings.

Sunnyhills Neighborhood Association (SNA) is working toward the goal of a PRT feeder from their neighborhood at the North end of Milpitas, CA, to the BART/LRT/bus Transit Center at the South end of town 3.5 miles away. PRT is a new technology, so it makes sense to limit our risk by starting small with a minimal system of guideway and cabs to shuttle between two stations.

A minimal two-station PRT system could shuttle people and their stuff (bikes, wheelchairs, groceries, etc.) over Montague Expressway. People get into a "cab" at one station and ride to the station on the other side of Montague, like a horizontal elevator or ferry. There, they exit and continue to their destination. Such a demonstration/pilot project, costing about the same as a standard steel-and-concrete pedestrian bridge, will allow us to verify PRT technology before expanding the system to service other locations.

Such a demonstration system, requiring about 2800 feet of elevated guideway, is estimated to cost about $7.9M (2800' / 5280'/mile x $15M/mile for Skyweb Express), and will allow us to verify PRT technology before expanding the system to serve other locations.

Such a connection and alignment relies on these points:

  • The property owner, Santa Clara Valley Water District (SCVWD), grants an easement for PRT guideway. SCVWD has worked with the City of Milpitas to provide channel access in the past (often with the City picking up certain maintenance costs). By erecting the dual guideways on the northern edge of the Penitencia Creek East Channel, the 30-foot wide northern embankment/levee is mostly available for SCVWD equipment to maintain the channel. SCVWD does not have defined criteria for encroachments, but rather decides on a case-by-case basis. Because PRT guideways are small and easily routed, we expect to reach a mutually beneficial joint-use agreement with SCVWD for use of their 70' wide right-of-way. A permit will also likely be required from the California Department of Fish & Wildlife.

  • The parallel-running PG&E right-of-way is 50' wide and lies south of, and adjacent to, the SCVWD channel on both sides of Montague.

  • Because PG&E most likely will not grant PRT station access on their right-of-way (other than for a 16-foot high crossing), the eastern station cannot be sited on the PG&E property just east of Montague Expessway. Instead, the return loop and stations must be moved to the "new park" area just south of the Lyons Communities development, adjacent to the SCVWD channel.

  • Skyweb Express guideways and vehicles can negotiate turns with a mere 25' radius (50' diameter).

  • PG&E high-voltage lines running north-south on the east side of Montague Expressway are high enough for PRT to operate below them safely. A minimum for the Skyweb Express system would be 25 feet: 16 feet above grade + guideway height(3') + vehicle height(5') + 1 foot gap = 25 feet.

  • PRT cabs will go clockwise on this pilot project - heading East on the northern leg and West on the southern leg.

  • When the BART circulator is completed, the northern leg will become part of the loop, thus providing quicker delivery of more residents to the transit center than if cabs circulated the other direction.

  • The BART Circulator will proceed north toward the BART station along the eastern border of the "new park" and the Lyons Communities development above the planned 26'-wide access road/fire lane (for details, see page 17 of this City document), across Capitol Avenue and under the 25' elevated LRT into the BART station.

  • Estimated length of elevated guideway plus stations is about about 2800 feet. Estimated construction cost is $7.9M (2800' / 5280'/mile x $15M/mile).

  • Foot bridges across the creek channel and PG&E easement will be needed near each station to provide access across those barriers. (Both are being planned for construction, with the western crossing due for completion in 2015.)

After the pilot project proves successful, then we could create our first area-wide loop. The most obvious location to include in that first loop is the new Milpitas BART station scheduled to open in 2017. A one-loop circulator could connect nearby areas with the BART/LRT/bus station. Major roadways, railroad tracks and a creek separate BART from high-density housing, the Great Mall, The Pines neighborhood, and a new elementary school and public park currently under construction to serve the area.

Installation and Operation: Ground-level impact on the property owners (Santa Clara Valley Water District and PG&E) is expected to be minimal with 2' x 2' footings (spaced 50' to 90' apart) and 2' diameter poles supporting the guideway above. With the exception of the short construction time and time spent coordinating the project with the contractor, no other costs to SCVWD and PG&E are expected. Concerns about security and vandalism at the stations can be addressed by installing a motion-sensing and tracking video recorder system. The video stream could easily be linked to the police substation a short distance away at the Great Mall. Since PRT is a fun and humanizing technology that people embrace, less vandalism is expected.

Due to PRT's automatic, energy-efficient electric drive, operating costs are expected to be minimal. Since our "ferry" will likely be an initial site for some PRT company, it's arguable that the company should absorb all maintenance (and any unexpected operating) costs for the first years so they can collect data. After that, O&M is so small that a nominal fee (say $0.25 per crossing) would likely cover it. If the two-station crossing is expanded into a BART circulator or multi-station, networked feeder system, O&M would be covered at the system level.

Advantages to Early Adoption: As an early adopter of PRT technology, Milpitas will enjoy a funding advantage for both the initial installation and subsequent extensions. Extensions beyond the BART circulator would likely include high-value destinations like the Library, City Hall, medical clinic, shopping centers, Sports Center and Senior Center. As the system grows and connects with other popular destinations, it becomes dramatically more useful. Because PRT is scalable, we can grow the system over time as need and opportunities arise.

If a quick installation of this minimal system results in the first PRT system in the USA, Milpitas will have another showpiece to attract tourists (and their dollars) and major media coverage. Some judicious promotion by the City's Economic Development team could attract lots of favorable publicity and business opportunities. Expect synergy when PRT is added to the Great Mall, transit hub and the entire Transit Area Specific Plan.

Why this matters to the world: The solution to getting people out of their cars in transit-deficient areas of the U.S. has eluded professional transportation planners. While most transit planners struggle to reduce single-occupancy vehicle (SOV) miles by a few percent, Personal Rapid Transit (PRT) combined with existing transit options and modern technology can reduce SOV rates by 50% according to this study of a business park in Palo Alto, CA.

Combined with scalability, PRT promises a much brighter transportation future – one using far less energy and resources while providing better service than the personal automobile. PRT offers a "Small is Beautiful" approach to transportation, and that’s a future worth exploring with this project.

Who will take these actions?

Milpitas City Hall, 455 E Calaveras Blvd, Milpitas, CA 95035The City of Milpitas is the most logical lead.

Historically, local transit projects have been subsidized by the Valley Transportation Authority (VTA) at the 80% level, leaving the City to come up with the other 20%. A special Bay Area transit fund (OBAG) could reduce the City's ante to only 12%.

Alternatively, VTA's interest in promoting use of the BART transit hub would make it a likely candidate to lead this project. Success in Milpitas could lead to a connection between the airport (SJS) and the train station (Diridon Station) followed by an area-wide network that would reduce expenses currently planned.

As a new solution that promises to dramatically reduce CO2 emissions in the transportation sector, other government agencies, foundations and environmental groups may also provide support.

Where will these actions be taken?

Although similar projects could be built in thousands of cities across the world and applied to many specific applications, SNA is proposing this project be located in southern Milpitas, CA:

In addition, specify the country or countries where these actions will be taken.

United States

Country 2

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Country 3

No country selected

Country 4

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Country 5

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What impact will these actions have on greenhouse gas emissions and/or adapting to climate change?

Although an elevated transportation system is less vulnerable to climate change-induced flooding, the primary environmental value of PRT is reduced CO2 emission in the transportation sector.

PRT offers a clean and efficient way to move people and stuff due to electricity-powered vehicles running non-stop on a smooth guideway. Although this project will move people, a wide-area PRT network could also move packages from centralized warehouses to neighborhoods for last-mile delivery to the ultimate address. Other PRT cabs could be modified to move trash and recyclable materials to centralized processing locations. In each instance, clean electric vehicles would be substituting for carbon-fueled vehicles - thus reducing CO2 emissions.

The wider the network, the more impact - geometrically! Like the Internet and other networks, each added node increases the value of the network more than that individual increment.

However, even a small system can make a big difference n moving people. Synergies between transportation options enabled by PRT makes a bigger-than-expected impact. As outlined in the diagram below, PRT combined with existing transit options and modern technology can reduce SOV rates by 50% according to this study of a business park in Palo Alto, CA.

PRT is a sustainable, carbon-free transportation system that can be privately or publicly financed. PRT has the potential to rapidly de-carbonize transportation by replacing fossil-fueled cars, buses, trains, and trucks while supporting the use of clean alternatives.  The implications are enormous because transportation accounts for about 1/4 to 1/3 of worldwide greenhouse gas emissions. 

What are other key benefits?

Material Resources: Due to the light-weight nature of PRT technology, far fewer resources are needed to provide capacity comparable to many other transportation options (cars, trucks, buses, LRT, trains). As a public transit system, PRT cabs would be shared, thus reducing the number of vehicles required to serve a population.

Click for high-resolution image.Personal Time: Perhaps our most limited resource is time. An automated transportation system that offers 95% cab availability at your nearby PRT station frees up time driving/parking or waiting for fixed-schedule transit.

Scalability: Because PRT is scalable, we can grow the system over time as need and opportunities arise.

Viral Growth: Because PRT is adaptable to most locations without much disruption of existing infrastructure, projects could be started in many places simultaneously. Using an open-source hardware design such as proposed by Intelligent Transportation Network System makes the process easier and cheaper. Viral growth of solutions is needed as we face a rapidly accelerating climate change problem.

Additional benefits arise in these areas:

  • Much of our crumbling infrastructure can be replaced with PRT technology at a lower cost than repairing and maintaining the existing roadways and railways.
  • Due to reduced runoff pollution from roads, we can expect cleaner water.
  • Elevated PRT can operate when streets are flooded.
  • By providing an alternative to inconvenient buses and expensive cars, PRT addresses one aspect of income inequality.
  • Using clean electric power, PRT improves air quality and lowers pollution that is related to many heath problems. 
  • Solar-powered transportation reduces the need for imported energy and increases energy security.
  • PRT is thousands of times safer than cars, so we can expect a reduction in the 40,000 annual auto-related deaths in the U.S.


What are the proposal’s projected costs?

This BART Circulator loop is about 17,000 feet, or 3.2 miles long. Using an industry-accepted estimate of $15M/mile, such a loop would cost about $48M. It would also eliminate the need for 3 pedestrian/cyclist overcrossings of barriers in the area, each costing over $10M.

Click for more information on the cost of PRT technology.

While capital costs to build a PRT network are less than many transit options, the higher value to a community offsets much of those costs. Operations and maintenance is comparable or lower than for traditional transit options.


After the first electric streetcars were demonstrated in the U.S. in 1885 and 1886, the technology spread rapidly. By 1895 almost 900 electric street railways and nearly 11,000 miles (18,000 km) of track had been built in the United States.

A successful demonstration with this BART Circulator could lead to a similar rapid deployment of the technology - and make a huge impact on transportation options and carbon emissions in a mere 10 years.

PRT proponents envision large PRT networks covering metropolitan areas. Given the scalability and parallel construction factors, such an opportunity could be realized within 15 years.

Click for enlarged image.

Pictured above is a 60-foot section of guidway ready for transport to an installation site.

About the author(s)

After a 20-year career in computer programming (communications), Mr. Means left corporate America in 1992 to work on community-oriented projects. His continuous involvement since then with the Sunnyhills Neighborhood Association (SNA) has supported community building, local activism, and on-the-ground improvements. As an SNA event champion, Mr. Means spearheaded three annual Bike and Roller Fests. His on-going commitment over the years ensured the completion of the Hetch-Hetchy linear trail through Sunnyhills, a two-mile long linear park/trail that stretches from Town Center to the northern city limits.

During his ten-year tenure on the Bicycle Transportation Advisory Commission (now BPAC) he got the ball rolling for the planning and construction of creekside trails in Milpitas. During that time, he was instrumental in putting the Yosemite/Curtis crossing of the railroad tracks (near the Great Mall) on the Bicycle Master Plan, Trails Master Plan, and Mid-Town Plan.

In '96, he discovered e-bikes and soon started a small business promoting, selling and servicing electric bikes and scooters. That role exposed him to the fundamental efficiencies of light-weight electric vehicles (LEVs) and advanced transit options which he continues to support through his website:

Today, after concluding that big changes are rapidly approaching, Mr. Means shifted from small business owner to community activist on behalf of advanced transit, democracy, and the environment. Much of his work in the democracy movement can be found at

Mr. Means is currently President of the Santa Clara County Democratic Club. Rob has lived in Milpitas since 1977, and shares his home with a wonderful wife and three cats.

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PRT Capacity:

PRT Cost:

Advanced Transit Association:

ATN/PRT Videos:

This 3-minute animated video outlines what PRT is and how it works.

introductory 3-minute video


Starting with an animated exploration of ways PRT can blend with city infrastructure, this 5-minute video ends with the real application at Heathrow Airport.

Click to watch video introduction to real-world PRT application (Heathrow Airport).