There is no single definition of a city, much less a smart city. The most that one can say about the latter is that it is where the internet of things (IOT) and analytics are applied to public infrastructure, services and participation in the community. However, as a thought experiment, if we generalized across some of the common rationales for applying the IOT to create smart cities – sustainability, livability, social equity, economic vitality, resilience and so on – which areas of focus should an aspiring smart city start with? Which areas might have a disproportionate impact, and thus give the greatest smart city bang for the buck?

In answering this, I have deliberately tried to look past the technology components – power supply, network connectivity, computing, a sensor fabric and so on – and focus on areas of smart city business and activity. My admittedly very tentative conclusions are set out below. I positively welcome reasoned disagreement as an aid to further developing my own ideas!

Advanced Meter Infrastructures (AMI)

The first of the smart city focus areas shown is AMI – telemetered energy and water meters that provide a continuous record of consumption. Visualizing the impact of AMI in concentric circles, at the center you would have the efficiencies that they enable in billing and account management (for example remote connect/disconnect). Moving out one ring, one would list the consumer service benefits that come from a continuous record of consumption – enabling consumers to manage their consumption (and so, reducing their environmental footprint and potentially, helping them to alleviate energy poverty. The value is amplified when smart meters are supported by the smart-phone apps that many meter vendors or utilities now also provide.

At the next ring out, by rapidly highlighting consumption anomalies, and when supported by meters and sensors on the distribution system, AMI enables fault detection and resilience, including where energy meters help with outage detection and water meters with leak detection. Such meters can also help highlight the impact of major events like floods or tornadoes. Some utilities have found that they can track the direction of tornadoes, for example, by “pinging” all their meters and tracking which meters no longer reply; and a well metered water system should (provided that the communications system remains intact) be able to report where a flood or earthquake just broke it, and which leaks are most severe.

Moving then to the outermost ring, you have the role that energy AMI plays in enabling many other smart grid technologies, such as distributed energy resources (DER), microgrids and demand response, all of which require accurate timing and measurement of consumption or supply to function.

In summary – AMI is a direct enabler of potential smart city goals concerning operating efficiency, customer service, sustainability and potentially, resilience. In enabling consumers to manage their consumption, and also in enabling microgrids, it can also be an enabler of social equity. Plenty of “bang for the buck” there!

Smart Street Lights

Smart street lights are LED-powered lights with internet connectivity to enable fault reporting and localized adjustment of light intensity and color. Using the same concentric rings construct as for AMI, at the center you would have operating efficiencies: reduced energy consumption (street lighting can account for as much as 50% of some cities’ total electricity usage) and also reductions in maintenance costs from the greater reliability and longer life of LEDs.

The next ring out would give you a series of customer or public service benefits from the smart street light itself. LEDs are brighter; and in many cases their light temperature can be varied, for example for different driving conditions such as snow or fog and to avoid the health concerns associated with excessive exposure to blue-white light. They can be linked to traffic sensors so that they brighten when people or cars are present, and dim when they are not, so saving further energy. They can also be made to brighten when an accident or a gunshot is detected, or when a crime is reported; and they could also be made to brighten or change color to show evacuation routes. Finally, LED lights are more easily focused downwards, so reducing night-time light pollution in urban areas.

The final ring would then consist of benefits that come from the fact that with their network connectivity and the physical light pole, they provide both a physical and virtual platform for other sensor applications. Those that I have seen or know to be under discussion include traffic and crime cameras; gunshot detection; air quality sensors; weather instruments; flooding sensors; and variable road signs. I do not claim that this is an exhaustive list!

Summarizing the smart city “bang for the buck” from smart street lights, we have significant contributions to operating efficiency, sustainability, transportation and public safety. The latter two further support economic vitality and livability. Further benefits may also arise depending on which other sensors are added to the light poles.

Smart Buildings

Smart buildings are defined here as buildings that deploy IOT and sustainable building technologies to reduce energy and water consumption, reduce waste, and/or offer additional benefits to the occupants.

As with AMI and smart lighting, the core benefit is efficiency, in this case in the form of reduced energy and water consumption. If the building design is extended to include technologies such as roof-top energy generation and water recycling, then it is increasingly possible to create, at reasonable cost, zero net impact buildings. Smart buildings may also incorporate green roofs, both to help manage temperature and heat island effects, and also to delay storm water run-off.

Moving to the next ring out, smart buildings frequently use their networks to incorporate sensors to maximize comfort or improve safety – these might include anything from crowd management cameras in stadia or shopping malls, to water quality sensors and warning systems. At least one university I know of includes CO2 sensors in its classrooms, to trigger the air-conditioning when CO2 levels become too high, to make sure that the students stay awake and attentive!

At the outermost ring, there are benefits that come from having multiple smart buildings in an area. For example, they might collectively enable energy demand aggregation for demand response or micro-grid enablement, so furthering the city’s environmental effect. Finally, given the frequency with which cities like to publicize the green buildings they have, it is evident that green buildings confer something of a “halo effect” on the city itself.

The smart city “bang for the buck” from smart buildings, then, includes efficiency and sustainability, public health and public safety, and a no-doubt welcome burnishing of the city’s reputation.

Smart Vehicles

I use the term “smart vehicles” to include both electric (EV) and autonomous (AV) vehicles, as they offer overlapping benefits and seem frequently to coincide in the same vehicles. These will not be commonplace for some years, but the breadth of their smart city impact will be so substantial that they merit inclusion.

The core ring for smart vehicles would consist of the ability of smart vehicles (when powered by energy from a relatively clean source, and after the impact of making the battery is allowed for), to reduce GHG and particulate emissions. This in turn has further localized environmental benefits such as healthier vegetation and reduced hydrocarbon content in run-off; and health benefits from reduced ingestion of particulates. In addition, EVs are quieter.

Moving then to the next ring out, energy companies are beginning to think seriously about the role that EV batteries can play in grid balancing and demand response, so maximizing the use of renewables. AVs will use the road more efficiently, reducing traffic congestion; they will become safer than human drivers; and in their likely ability to take themselves from one user to the next, and so minimizing downtime, they seem likely to encourage whole new modes of ownership and access. As they do this they will reduce the need for city parking, which may enable new approaches to city planning.

The smart city “bang for the buck” from EVs and AVs has yet fully to be identified, but at the very least it seems likely that it will help address the sustainability, mobility, safety and livability objectives of smart cities, and potentially those relating to social equity too.

Open Data

The final area of disproportionate impact that I want to note is open data, defined to include any data either made available to or collected by the public and used to monitor or improve the level of service offered by the smart city.

The role of open data lies in engaging and empowering citizens with greater understanding of how their city works and how to access what it has to offer; and in enabling citizens themselves to generate improvements to their communities and neighborhoods. One of the weaknesses of smart cities is the risk that the technology will become all-encompassing and so, alienating and disenfranchising. Some writers accordingly portray smart cities as profoundly authoritarian and anti-democratic. The antidotes to this, that would allow us to have the undoubted benefits that smart cities can offer while avoiding the adverse consequences, include the transparency; mutual support and encouragement, and feedback to politicians and managers that open data enables. I have described this elsewhere as the “U-Shaped” model, enhancing top-down (government to citizen) service provision with side-to-side (citizen to citizen) and bottom-up (citizen to government) flows of data and activity. It’s tough to identify concentric rings for open data – just one single, very wide one!


The five application areas just discussed, taken together, will not of themselves deliver a smart city, and there are numerous other extremely worthwhile smart city technologies. However, I believe that these five areas together will, if fully exploited, deliver much of the promise of smart cities and can be thought of as a very functional “starter set”.