Proffers for New Development in Fairfax County, Virginia 
Fairfax County established Transportation Demand Management (TDM) requirements (“proffers”) for new development that would have significant traffic impacts. For buildings within the urban centre of Tysons, trips had to be reduced between 25% and 65% during peak hours, depending on the size of the building and its proximity to the Metrorail stations. The county proffers required large new properties to annually monitor trips, conduct tenant commuting surveys, and show that they were meeting their trip reduction goals. They also had to conduct surveys every three years. Over seven years, 13 such developments generated 63% fewer trips, which was 34% beyond their goals. For the office buildings, this was likely at least partly a result of more people working from home during the COVID pandemic.
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Carpooling Promotion in Paris 
France provides financial incentives to local travel authorities (LTAs), employers and employees to promote carpooling. It also funds the development of carpooling infrastructure, ridesharing platforms that make it much easier to carpool, and fraud prevention mechanisms. This case study covers the formative research and early implementation in Paris of France’s National Daily Carpooling Plan.
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Coolfood
Coolfood – World Resources Institute’s (WRI) initiative for curbing diet-related emissions – provides the food service industry with the tools and expertise to reduce emissions by 25% by 2030, in line with the goals of the Paris Agreement.
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Smart Trips Austin
Smart Trips Austin encourages residents of Austin Texas, USA to take multi-modal transportation options (walk, bike, ride transit, and share rides) more often, rather than drive alone. The program focuses on personal interactions — educating individuals on their options and overcoming barriers to multi-modal travel. Smart Trips reinforces this new information using community-based programs such as learn-to-ride classes, transit instruction, and group walking activities. Initially, the program targeted residential neighbourhoods of Austin Texas; each year a different area was targeted. In 2020 the program expanded to city-wide and began to segment using a Stages of Change approach. In 2021, it started targeting residents who had recently moved to or around Austin. Smart Trips Austin averaged a participation rate of 5-10% of households contacted, a 5-10% reduction in drive-alone trips among participants (about 41,000 vehicle trips per year), and a corresponding 5-10% increase in active and shared trips. This account of the program was designated a Landmark case study in 2023, making the City of Austin one of the few governments with more than one program designation.
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Fridge Night / Use Up Day
The Fridge Night programme offers simple, practical solutions to help people be more resourceful with and enjoy eating the food they have at home, thereby reducing food waste and associated greenhouse gas emissions. Participants pledge to use up expiring perishables one evening a week for a month, and complete weekly challenges. They are sent reminders and tips. In return, they save time and money and get tools for easily planning meals with leftovers.
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Flashfood
According to Second Harvest, almost 60% (35.5 million metric tonnes) of food produced in Canada is wasted annually. Roughly 32% (1.2 million tonnes) is still edible. The app informs users about local food nearing its best before date, often discounted by 50% or more. While some items may only be usable for a day or two, others can last for weeks – especially if frozen or cooked. The Flashfood app enables food stores to sell food that would otherwise be thrown out, while reducing their carbon footprint. Consumers are able buy food that they would otherwise deem too expensive.
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Co-Ownership of Wind Farms
What if you want to move away from gas and oil, but rent, are about to move, or can’t afford solar panels? If your energy supplier has not already pledged to go green, you have few options. The co-ownership of wind farms engages and makes it practical for more homeowners and renters to buy wind-generated power.
Liftshare and Mobilityways, U.K.
Liftshare is a social enterprise that has worked with over 700 of the UK’s largest employers to reduce the number of single occupancy vehicle trips using carsharing, active transportation and public transit when commuting for work. With an online community of over 1 million members, it is estimated that Liftshare members have avoided the release of 300 million kg / 300,000 tonnes of commuter carbon emissions (averaging 50 million kg / 50,000 tonnes per year). In 2020, Liftshare launched Mobilityways, a sister platform that enables employers to evidence, track, plan and change their commuter emissions via a set of tools / modules that work seamlessly together.
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Southern Nevada Water Authority's Water Smart Landscapes Program
As climate change leads to more drought situations, it will be important to understand how to best promote water conservation. Southern Nevada Water Authority’s Water Smart Landscapes (WSL) program pays homeowners to replace their non-native, ornamental lawns with plants and landscapes that use less water because they are better adapted to their dry climate. It is one of the longest running “cash for grass” policies. Designated a Landmark case study by our climate change peer review panel in 2022.
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Reduce Your Juice: Meaningful Gamification Motivates and Empowers a Challenging Consumer Segment to Save Money and Energy
This innovative social marketing approach changed the energy use behaviours of low-income renters in Brisbane, Australia, through meaningful gamification. The gamified experience promoted desired behaviours and reduced undesired ones, all carefully chosen using McKenzie-Mohr's cbsm guidelines for selecting behaviors. The Reduce Your Juice program was designed to be fun, easy and impactful. On the exterior, it appears as a simple, fun and easy experience of games and gamified activities, communications, community, and rewards. However, below the surface lies a sophisticated intervention developed through the application of formative research and theory and implemented by a team of multi-disciplinary experts from the energy, social marketing, behaviour change, digital insights & technology, research, and social sectors. Designated a Landmark case study by our Building Energy peer review panel in 2022.
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Chicago’s Building Energy Rating System
Chicago was the first U.S. city to require building owners to prominently post a building’s energy performance rating, and to share that that rating with potential buyers and/or renters. While the rating system was being introduced, ComEd and Peoples Gas ran extensive complementary incentive and rebate programs that enabled building owners and managers to make energy improvements at little to no cost. Designated a Landmark case study in 2022 by our climate change peer review panel.
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How Copenhagen Became a Cycling City 
What makes a great cycling city? How did the medium-sized City of Copenhagen get its citizens to cycle to work / school 49% of the time? While topography and climate are significant influencers, safety, supportive infrastructure, and promotion also played key roles. Copenhagen increased cycling by making it safer, easier, and more convenient. This case illustrates the power of piloting alternative enhancements on an ongoing basis to further reduce barriers and increase benefits, based on regular surveys, traffic data and safety data. It also features a transparent planning process - the Bicycle Account – a research, evaluation, promotion, and citizen engagement tool used every two years since 1996. Designated a Landmark case study by our Transportation peer selection panel in 2022.
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Paris Reduces Car Use, Boosts Walking and Cycling
Paris is an inspiration for large cities around the world, having reduced car traffic in its core (Ile de France) from a mode share of 12.8% in 2010 to 6% in 2020. How did Paris get to be one of the cities in the world with the lowest mode share for single occupant vehicles? The city is comparatively dense and has one of the top subways in the world. But what is most striking about its transformation is the increase in cycling and walking during this period – they increased from 55.4% in 2010 to 68% in 2020. Numerous programs offered by three levels of government explicitly prioritized bicycles over cars and reduced on-street car parking to make room for bike lanes. They taxed and restricted more polluting vehicles, and gradually phased them out, while providing a conversion bonus for the purchase or lease of electric-assisted bicycles and cargo bikes. In addition, car ads had to include messages promoting greener methods of transportation, and incentives were provided for bike repairs and tune-ups. Designated a Landmark case study by our sustainable transportation peer review and selection panel in 2022.
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Opting Out in Germany for Non-Renewable Energy
While many people in Germany say they would use green energy if presented with a choice, very few consumers do so. In contrast, most people have been using green energy in a few German municipalities where citizens have had to opt out for non-renewable energy supplies rather than having to opt-in to get renewable ones. This case study also illustrates the connection between green power choices and clean air / environmental health, and the value of randomized control trials (RCTs) for measuring program impacts. Designated a Landmark case study by our Building Energy peer review panel in 2022.
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Too Good to Go
About 75% of food waste goes to landfill, where it becomes one of the largest sources of greenhouse gas emissions at 10% of total emissions. Too Good to Go turns food waste into a win-win situation for everyone, by creating jobs, generating revenue, reducing food waste, and diminishing environmental impacts. At its most basic, the app is a marketplace for surplus food. It enables you to see what extra food is likely to be available that day from nearby bakeries, stores, and restaurants - fresh food that would otherwise be thrown out at the end of the day because it would no longer be considered fresh and salable. Using the app, you can buy a ‘magic bag’ meal for roughly one third of what you would normally pay, then pick it up at the vendor’s closing time. As of June 2022, a total of 141 million bags had been sold, eliminating 775 million lb. (about 387,500 US tons) of CO2 emissions. In the first six months of 2022 alone, 88.5 million bags were sold, eliminating the equivalent of 973.5 million pounds (about 486,800 US tons) of CO2 emissions per year.
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Carpooling and Vanpooling in San Mateo County, California
This program promotes carpooling and vanpooling instead of driving alone during peak commute periods, using advertising (online, video, and display), challenges, and prize-based campaigns to attract and retain its target audience. It also made its standard Guaranteed Ride Home system easier to use. This case study illustrates the timing of incentives to promote habit formation. It also exemplifies how benefits can be increased by integrating some of the participant-facing aspects of multiple, independent programs in neighboring regions.
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Energy Cat Game
The Energy Cat computer game was piloted with social housing residents in Plymouth, United Kingdom, to motivate and help them learn about affordable, energy-saving steps they could take in their homes. The game provided an average electricity saving of 3.46% and an average gas saving of 7.48%.
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Solarize Boosts Installations and Transforms Solar Markets Across America
Solarize is a group purchase program designed to simplify and reduce the cost of investing in solar energy. The campaign organizes a volunteer committee of residents to competitively select a solar installer who agrees to set pricing. At a series of free educational workshops participants can learn about the technology, incentives, and financing options. Interested, participants can then sign up for a free site assessment and are guaranteed the Solarize price, if they sign a contract within the campaign timeline. Customers can save as much as 25% of the total cost of installation. This approach enables grassroot and other solar advocates to build motivation and engagement over time, reduce key barriers to action, convert “interest” into “action”, and permanently transform the market for solar installations in their communities. Resulting installations generated 62,000,000 kWh of clean energy supply each year. Designated a Landmark case study by our Building Energy peer review panel in 2021.
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Virgin Atlantic’s Airline Captains Improve Fuel Efficiency
Virgin Atlantic Airways (VAA) conducted an eight-month pilot in 2014 to test the potential roles and impacts of monitoring, performance information, personal targets, and prosocial incentives on the fuel-use behavior of their captains. All 335 of VAA’s captains were part of the pilot, and they were randomly assigned to four separate treatment groups. Since the pilot, the approach has become business as usual at VAA, and the technology was commercialized through Signol and updated to a web-app and email rather than post. Designated a Landmark case study in 2021.
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Climate Matters Program for TV Weathercasters
Climate Matters trains and supports American TV weathercasters to report on the local impacts of climate change while reflecting current scientific knowledge and concerns. The program provides participating newscasters with weekly story packages with local data and broadcast-quality graphics that visualize the data. Because of an overt conflict in the meteorology community about opposing views of climate change, the program engaged a conflict mediator who worked with small groups of opinion-leading weathercasters to surface and work through the entrenched conflicts. As climate reporting became increasingly normative, the program ensured that everyone in the weathercasting community knew the behaviors were gaining in popularity. As of 31 October 2020, there were 968 participating weathercasters in 483 local TV stations, in 92% of all US media markets and 99 of the top 100 media markets. Viewers exposed to their climate education became more likely to understand that climate change is already a 'here, now, us' problem. Designated a Landmark case study in 2021.
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Day Zero: Cape Town Includes Fear Appeal to Avoid Running Out of Water
Fear appeals must be carefully considered as they can too-easily backfire and discourage people from taking in and acting on our messages. And why spread fear unnecessarily? This case study illustrates an appropriate and effective use of a fear appeal to reduce water consumption in Cape Town South Africa. It tracks 30 years, from the time the City predicted severe water shortages to the point where the taps nearly ran dry and this city of four million people reduced water use enough to avoid disaster. Designated a Landmark case study in 2021.
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WaterSense Adds Up to Big Water and Energy Savings
WaterSense, a partnership program sponsored by the U.S. Environmental Protection Agency (EPA), seeks to protect the future of the nation’s water supply by offering Americans a simple way to use less water with water-efficient products, homes, and services. WaterSense labeled products, which are independently certified to use at least 20% less water and perform as well or better than standard models, have been on the market since 2007. As of 2021 there are more than 30,000 labeled models, including products used in residential and commercial bathrooms, and outdoor irrigation. EPA’s WaterSense program has also certified over 3,000 homes with WaterSense labeled fixtures and water-efficient features. By 2020 it had saved 5.3 trillion gallons of water and 603 billion kWh of electricity. Designated a Landmark case study by our Building Energy peer review panel in 2021.
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TDM at Seattle Children’s Hospital
Seattle Children’s Hospital has operated a widely recognized trip reduction program since 1995. This program is an early and successful example of providing drivers with cash incentives to offset losing free parking (“parking cash out”). It is also one of the few ongoing examples of a program that pays people if they take a non-SOV way to work. Between 1995 and 2017, the percentage of employees who drive to work alone dropped from 73% to 33%. Further, the program’s commuting perks have helped attract & retain quality employees, and the program has enabled the hospital to avoid spending $20 million to build new parking facilities. Designated a Landmark (best practice) case study in 2021.
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Carbon Cure
To meet global greenhouse gas targets, we will need to remove carbon dioxide (CO2) from the atmosphere, not just slow down emissions. Carbon Cure was designed to promote a shift in specification and purchasing behaviors across the construction supply chain, to recapture a significant amount of carbon dioxide from the atmosphere and help abate climate change. This case study focuses on how the company has promoted the rapid adoption by concrete plants of a new type of concrete – one that in its manufacturing process, removes and permanently stores significant amounts of carbon from the atmosphere. By 2021 it had enabled the capture of 142,046,000 lb. of CO2 over nine years, an average of 15,782,889 lb. / year.
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Norway’s Promotion of Electric Vehicles
Several policies / incentives, in place over an extended period, have made Norwegians more likely to purchase electric vehicles (EVs) than people in any other country. These incentives have included: exemption from vehicle registration and high purchase taxes, reduced road tolls, free parking, and access to some bus lanes. A similar long-term approach could be adapted for other big-ticket purchasing behaviors where the impact justifies the expense – for example energy-efficient home / building retrofits and appliances. Norway's electric cars are close to zero-emission as 98% of its electricity came from hydropower.
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Canada-Wide Ban on Menthol Cigarettes
Bans on menthol cigarettes across Canada from 2015 to 2017 led to a significant increase in the numbers of smokers who attempted to quit and who quit successfully, while reducing relapse rates among former smokers. Canada was the one of the first countries to implement a ban on menthol cigarettes, and the first country where such a ban was evaluated.
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Heat Loss Images, Norm Appeals Raise Impacts in Medicine Hat
A Randomized Controlled Trial tested the impacts of providing consumers, on their monthly utility bills, with high-resolution infrared images of their houses, information about their heat loss relative to their neighbors, and estimated savings from improving their home’s insulation and air tightness. This treatment was twice as effective as a traditional Home Energy Report (HER) treatment. This demonstrates the power of visual cues that help make the intangible more vivid, concrete, and actionable. This case study also illustrates how norm appeals can backfire when descriptive norms are provided to those who are already doing “better” than most, without also providing an affirming injunctive norm. Designated a Landmark case study in 2020.
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Seattle’s Just One Trip Phase II
Just One Trip Phase II illustrates the use of Propensity Modelling / Predictive Analysis, Street Ambassadors, Quality Online User Experience (UX), and trip planning to reduce the proportion of single-occupant car trips in Seattle WA, USA. It engaged over 21,000 people and on average participants reduced four drive-alone trips per week per person. Designated a Landmark case study in 2020.
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City of Austin’s Leave Time Travel Incentive
The City of Austin reduced employee commute travel by one million vehicle miles within six months of making its Leave Time Reward (LTR) a permanent incentive. During this period, the percentage of drive-alone trips fell from 53% to 41%. Attribution of these impacts to the City’s time off incentive policy is strengthened because that policy was introduced in the pilot study, then withdrawn after the pilot, then later reintroduced for the permanent program (Reversal Design.) Designated a Landmark case study in 2020.
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Way to Go Durham
This case study covers the formative research and pilot testing of the City of Durham’s Way to Go program with City staff and local university students. It illustrates the value of A/B testing and Randomized Control Trials for evaluating alternative program tactics. It exemplifies the effective use of personalized commute plans distributed en-masse and shows that they can have a substantial impact on travel behavior, even with no added incentives.
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