Smart city graphic

Greening a Smart City

How do we keep air clean, our carbon footprint low, the population healthy and the environment green?

The quest for a ‘smart’ city has exposed the damning evidence of energy and environmental dangers by using Big Data. Analysing around architecture, the behaviours of the public and other aspects shows what needs to be done in order to improve the environment we live in.

A rapidly growing global population means that we will need to exploit a space’s potential, whether it is taller sustainable buildings, innovative waste management, or better renewable processes. One of the biggest priorities when creating a smart city is to keep it eco-friendly and for us to work towards a cleaner, greener future. We need to look at sustainable buildings - according to interactive platform Urban Hub, about 250 million new housing units will be required before 2030 in the 12 most populated countries, which account for 61 per cent of the global population.

This need for housing means that we must be smart with space saving, maximising the potential of smaller areas by building greener, cheaper and cleaner high-rise constructions with smart energy management.

Buildings are currently the largest consumers of electricity, with offices and workplaces accounting for 40 per cent of total energy usage in cities. However, global energy consumption could be reduced by 10 per cent by 2030 if intelligent engineering and innovative technologies are employed during construction and refurbishment of buildings - their efficiency could be as much as doubled.

Building information modelling technology, or BIM, has had major impacts in the green technology field. It is so beneficial to boosting the sustainability of buildings that the UK government required its use in all public sector builds from April 2016. David Light, BIM consultant at Autodesk, says: “BIM is the use of a virtual 3D model which allows you to simulate and analyse building performance and, through data insight, helps you make the best sustainable and economic decisions possible for a project. Visualisations can be used to test out various sustainable methods prior to constructing the building.”

As an example, New York architects SHoP used BIM to map out the most sustainable features for the Botswana Innovation Hub based on its surrounding environment. “These included implementing ample overhangs to shade the structure and keep the building cool, reducing the reliance on air-conditioning, as well as a living roof that collects rain water for reuse,” Light says.

Optimum performance

An optimum-performance green building should be able to massively reduce environmental impacts in water, waste, materials, energy and carbon production.

Clare Wildfire, technical director of Mott MacDonald, believes that buildings and infrastructure “designed with non-essential high-embodied carbon elements should be removed, while essential high-embodied carbon elements are easily extracted and re-used at end of life.”

Philipp Schuster, MD UK of Loxone, says that by autonomously adapting and personalising a building’s ‘routine’ according to the occupants’ habits, we can reduce our carbon footprint further still. “Smart buildings are a significant contributing factor, with systems such as lighting, heating, blind control and solar panels all working in tandem to cut down the amount of energy used - optimising efficiency and comfort at the same time.

“Several heating solutions can already learn how long it takes to bring a room to temperature and guarantee that rooms are heated precisely. Fully integrated smart systems can go even further and autonomously adapt to a whole building’s routine.”

For example, Schuster says that during the day inhabitants can use self-produced electricity to run appliances, and then at night all devices left on standby are automatically switched off to reduce the need for imported electricity from the grid. “If systems like these are adopted, not just in single buildings but across an entire city, the collective energy saving would be enormous. Additionally, this can relieve the pressure on an already stretched national grid and provide cost savings that will update or expand the current infrastructure.”

Light says that this process doesn’t have to be limited to new builds; it can be applied to existing structures to improve sustainability. “In a retrofit, the building is captured with a camera, satellite images or a laser scan. 3D modelling technology can then be used by the architect to rapidly convert this captured data into simplified geometric forms of the existing structure.

“Then you run energy simulations that detail how energy usage can be optimised in a building. For example, predicting where the sun and its shadows are at every hour of every day of the year, which would clarify whether a structure would benefit from the installation of ‘cool rooftops’ or solar photovoltaic panels.”

Renovating existing buildings can make more efficient use of resources, minimising waste and easing up CO2 emissions, while maintaining their architecture and cultural impact. So far, integrating heating, ventilation and air conditioning and photovoltaic components - the method of converting solar energy into direct current electricity using semiconducting materials, like solar panels - in the front of buildings, updating glazing technologies and other construction components to minimise future energy consumption, effectively keeps the architecture’s façade as original as possible.

In Europe especially, with its long history and timeless architecture, widespread renovation is necessary for countless buildings to reduce their energy consumption. If an elevator were to be updated, for example, or replaced with escalators, it would cut the energy consumption massively - up to 60 per cent. The double-deck elevators at the Shanghai World Financial Centre are the fastest in the world at 36km/h; they also have the highest VDI 4701 Class A efficiency rating.

For a city to be smart, Green Capacity says that buildings must be understood as an integrated part of the entire system, but a building’s sustainability is hard to uphold in an unsustainable society. To create a healthy society, it is important to construct a system where renewable energy is continually transported - through smart grids - and water and waste is effectively managed.

According to Urban Hub, the global demand for energy will increase by 20 to 35 per cent in the next 15 years, with cities consuming almost two-thirds of that increase. This could spell disaster for the environment if energy is not cleanly and sustainably sourced.

In a smart city, areas will need to be used to their maximum efficiency. Technology will need to be savvy, intelligent and space-saving, and keep up with the energy demands of a growing population.

Renewables around the world


In the last decade we have seen an upsurge in the use of renewable energies. Solar panels, for example, are increasingly materialising around the UK. Unused land and roofs of council houses and properties seem to have become the residence of solar panels, with the idea of reducing energy bills while helping the government reach its carbon emission targets.

Thames Water installed the then-world’s biggest solar farm just outside London, using 23,000 floating panels - which can have a peak power output of 6.3MW- on the Queen Elizabeth II reservoir.

It’s not just the UK that is investing in solar panels. Japanese electronics multinational Kyocera began work on its self-proclaimed ‘biggest floating solar farm in the world’ in January. It is under construction in Japan’s Chiba prefecture and could supply 13.4MW of power when it is completed in early 2018.

It seems that solar energy is increasing in popularity all over the world: good news for the environment and our carbon footprint. In the US, for example, an innovative pilot project from Solar Roadways will involve the construction of a 150-square-foot (14m2) solar panel surface in Sandpoint ID. The start-up company develops the panels to replace cement on roads, paths and car parks. The panels have small heaters, solar panels and LED lights inside; the LEDs could mark the lines of the roads and the heaters could keep the roads ice- and snow-free. Co-founder Scott Brusaw told community newspaper the Inlander that the panels can withstand a load of 250,000lb (110,000kg).

In India, Piyush Goyal, the country’s energy minister, recently praised solar energy, saying that it is now cheaper than coal. Power realities are changing fast in spite of concerns over baseload and storage, with solar energy set to become more popular in the coming years. Goyal also expects India to go far beyond its goal of 100GW of solar power by 2022.

Nick Boyle, CEO of Lightsource Renewable Energy, Europe’s leading solar energy company, believes that solar will become even more closely woven into cities to meet increasing demand as time goes on. He says: “As space demands an ever-increasing premium, the UK’s solar revolution will be a vital component of smart cities of the future, providing an energy solution that is quick to deploy at scale and requires limited maintenance.

“Solar panels can be installed on ground, roof, and water and even into the fabric of buildings themselves through Building Integrated Photovoltaics (BIPV) – including solar roof tiles and technologies that can be used to convert windows and glass surfaces into working solar modules.”


Water is an abundant source of potential energy. Hydroelectric power is responsible for about one-fifth of the world’s electricity. From its humble beginnings in 1879 at Niagara Falls, this form of renewable energy is the cheapest way to generate electricity, despite its potential flaws in environmental disruption.

When we think of hydroelectric power, a typical hydro plant with a tremendous, sprawling dam may spring to mind. Start-ups and other companies are trying to harness water’s energy with the maximum output akin to a hydro plant, but on a much smaller scale - the sort of scale that would suit a smart, environmentally friendly city.

An example of a small-scale, maximum output appliance is Watly, a solar-powered computer that is a water purifier, generates electricity off-grid and provides Internet connectivity.

Marco A Attisani, CEO and founder of Watly, says that during 15 years of service, one Watly can save as much as 2,500 tonnes of greenhouse gas emissions (CO2) - equivalent to 5,250 barrels of oil - purify millions of litres of water and generate 1GWh of clean electricity.

“A single Watly stands alone, but several Watly units deployed across the globe are connected and constitute an ‘Energynet’ - the global smart-grid in which water and electricity fuse together with information technology.

“Not only does it work on the principle of becoming more environmentally friendly, it improves global living standards for people in the world.”

Attisani says that as technologies develop, there is a chance for cities to reap the social and environmental benefits. Watly machines are auto-powered, self-sustained and multi-functional. He adds that it is “a new concept of a smart city.

“Watly is an infrastructural solution that brings the three pillars of modern society: water, energy and Internet connectivity to power and accelerate an innovation that is conscious of its environmental impact.”


Wind energy is the world’s fastest growing source of renewable energy, and turbines are the most effective at capturing the wind’s power. There are currently 956 wind projects in the UK alone and RenewableUK says a single 2.5MW wind turbine can generate enough electricity to meet the annual needs of over 1,400 homes.

The increasing popularity of wind energy around the world implies that turbines on roofs, scattered throughout the smart city, could well be on the horizon.

Its growing acceptance as the go-to source for renewable energy was illustrated recently, with Germany’s Siemens winning a five-year deal worth up to £833m to construct and maintain 102 wind turbines for Scottish Power’s East Anglia ONE project off the coast of Norfolk, UK. The wind farm will be operational in 2020.


It isn’t just what you can see in the city that makes it sustainable. As well as reducing the waste in landfills, integrated waste management solutions lessen the rubbish tip and create energy for the electricity grid.

Globally, the total volume of waste is estimated to increase by almost 50 per cent in the next decade, so it is paramount that cities get to grips with refuse. It is hoped that traditional methods of waste management, such as landfills and diesel trucks, will evolve into smart recycling and bioenergy.

Bioenergy comes from biofuel, which is fuel produced from organic material (biomass) such as household food waste, animal waste and plant materials. There are now more innovative waste management technologies available than ever before, which will help our cities handle their waste and benefit from clean energy.

In the US, researchers from the University of California, Los Angeles have been creating new biofuels to increase alternative energy sources by using bacteria responsible for digestion and disease. This development could open up new doors for more eco-friendly fuel sources and less waste.

According to Department for Transport figures, 370 million litres of biofuel was supplied in the UK in the year to April 2016, which was only 2.85 per cent of total road and non-road mobile machinery fuel, and bioethanol comprised 73 per cent of supply.

Biogen, the UK’s leading operator of anaerobic digestion (AD) plants, processes almost a quarter of a million tonnes of food waste each year, which produces 11MW of green electricity for the grid. The AD process leaves a nutrient-rich biofertiliser which is used on the land for crops. If more plants like this were placed on smart cities’ borders, the environment would benefit enormously.

Mark Abbas, CEO of GMT, recommends monitoring the waste disposal behaviour of households using Big Data around population, architecture and other demographic characteristics. This data can be analysed and used to effectively improve the greening of cities.

He adds: “Looking at a lot of the smart city initiatives under way today, they seem to be happening independently of one another. In 10 years, we’ll have started to move away from these to increased interaction with benchmarking between cities to see where improvements can be made. What’s important is that information is made publicly accessible online to drive awareness around waste disposal behaviour.”

How do we store the energy?

Renewable energy can be built into the densest of cities if we can fix energy storage, says Traver Kennedy, CEO of Joi Scientific.

“With solar panels, wind turbines and emerging new technologies, buildings themselves can generate energy, but they need to be able to store that energy.

“Battery technologies are increasingly being piloted for this role, but while the world’s automotive giants rush to bring zero emission fuel cell electric vehicles (FCEVs) to our roads, we have only just joined the dots to realise that hydrogen is an ideal storage medium.

“Hydrogen can be burned or converted to electricity without producing carbon or air pollutants, but today it is derived from ‘dirty’ methane,” he explains.

Kennedy says that Joi Scientific has pioneered a new technology called Hydrogen 2.0, which allows the extraction of hydrogen from water on-demand at a price competitive to other alternatives.

He adds that “this enables safe energy storage and provides a fuel not just for hydrogen-powered cars, but for clean power generation in offices, data centres and apartment buildings that produces zero harmful emissions.

“The smart cities of the future will be greener because transport, industry, homes and businesses can all be powered by hydrogen - just add water.”

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