Barcelona: Spain’s Ciudad del Sol

Barcelona may be famous for Gaudí’s modernist architecture and its world-class Picasso museum, but there’s something else for which the city of 1.6 million should be known: its commitment to sustainability. In fact, Barcelona’s solar energy regulations have become a model for other municipalities, with more than 70 Spanish municipalities following the city’s example.

Solar Hot Water

In 2000, Barcelona became the first European city to have a solar thermal ordinance. All new buildings and existing buildings undergoing major renovations are required to use solar panels to supply 60 percent of their hot water requirements. Swimming pool heating must be met 100 percent from solar energy. The ordinance applies to all commercial buildings and all residential buildings with more than 16 apartments. This policy has increased the amount of solar thermal panels in the city 4,000%, from 1.1 square meters per 1,000 people in 2000 to over 40 square meters per 1,000 people today.

The policy has been so successful that 70 other municipalities in the country replicated it, and in 2006 the Spanish government became the first in the world to enact a national building code requiring the installation of solar panels for hot water.

Solar Pergola

In 2002, the city established the Barcelona Local Energy Agency, which initiated a 10-year plan for energy conservation and sustainable energy production, the Barcelona Energy Improvement Plan. The plan provided a set of 55 strategies ranging from energy conservation measures to education programs.

One part of the plan was to increase the use of solar energy not just for heating water but also for electricity. In 2004, Barcelona hosted the Universal Forum of Cultures, an international event held every three years to promote peace, sustainable development, human rights, and respect for cultural diversity. The site chosen for the event was in an industrial area on an extremely polluted river, known as the “Chernobyl on the river Besòs.” As part of revamping the area the city installed a 443-kilowatt PV array, the largest urban PV system in Europe at the time. This PV array, built as a pergola, creates shade, beautifies the area with interesting urban architecture, and feeds 554 MWh of power per year to Barcelona’s electric grid, reducing the city’s carbon emissions by 440 tonnes per year.

Two years later, in 2006, Barcelona passed a Solar Photovoltaic Ordinance requiring all buildings of certain sizes to use PV—all commercial buildings with a roof surface area over 3,500 square meters must produce 10 percent of their electricity consumption with PV, and office buildings with a minimum surface of 1,500 square meters must produce 12 percent of their electricity consumption with PV. All hotels and hospitals with over 100 beds must also incorporate PV systems.

There are also solar panels on the city hall, bus stops, schools, and libraries, bringing the total installed PV capacity in the city to 14 MW in 2008. By the end of 2011, Spain’s Catalonia region—of which Barcelona is the capital—had a cumulative installed solar PV capacity of 234 MW.

And to further reduce the City’s electric bill, Barcelona is retrofitting its streetlights with LED bulbs that run on motion sensors, with a goal of having 3,360 efficient street lamps on 160 streets by 2015. These wireless street lamps are expected to decrease the city’s municipal power bill by a third.

Putting Waste to Use

Another goal of the Barcelona Energy Improvement Plan was to greatly increase the city’s use of renewable energy sources. Besides the abundant solar energy that falls on Barcelona, the city also produces a lot of organic waste. City officials decided to use that waste for some of their heating and air conditioning needs.

In 2002, Barcelona installed a district heating and cooling system that relies on urban waste. The biomass for the CHP plant, called Districlima, comes from maintenance of the city’s numerous parks and gardens (approximately 7,200 metric tons per year) and maintenance of the outlying forests (another 28,000 tons per year). It has grown each year. A second power plant was added in 2012 to handle power peaks. There are now 15 kilometers of pipes and 80 connected public and private buildings, the largest district heating and cooling network in Spain, with 74 MW of cooling power and 52 MW of heating power. The system reduced CO2 emissions by 17,500 metric tons in 2013—the equivalent of planting 875,000 trees, six times more trees than the city currently has.

Tackling Transportation

However, the main emitter of greenhouse gas emissions in Barcelona was the transport sector. So part of the energy plan was developing public transport infrastructure. Barcelona’s transport system, Transports Metropolitan de Barcelona (TMB), runs all the city’s buses and the Metro. The TMB bus network, which transports 190 million passengers per year, has one of the cleanest bus fleets in Europe, with 400 natural gas vehicles, 82 hybrids, and the rest (approximately 500) with particulate traps that reduce annual emissions of NOx (71%) and particles (85%) for each bus. TMB is also currently testing a pure electric bus with a range of 120 miles, enough to cover a full-service urban line. The city also has more than 500 hybrid taxis, 294 municipal electric vehicles (such as for trash collection and streetlight maintenance), 262 public charging stations, 130 electric motorbikes, and an estimated 400 private electric vehicles on its streets.

Bicing is Barcelona’s bike share program, inaugurated in 2007. Bicing has 6,000 bicycles at 400 stations throughout the city. There are currently over 121,000 users generating 14 million trips per year on the city’s 181 kilometers of bike lanes. Approximately 50 percent of all trips in the city are currently made on foot or on bicycle, and only 20 percent of trips in the city are made by private vehicles. Barcelona also launched the world’s first electric scooter sharing program, MOTIT. All a commuter needs is a smartphone to reserve a scooter that can be picked up and dropped off at numerous locations around the city. The bright purple scooters go 40–60 kilometers on a single charge and even come equipped with a helmet.

The City also implemented smart parking spaces to help reduce the amount of time spent searching for parking. Sensors detect if a parking spot is vacant, and drivers can get the info on their smartphones. The sensors also provide data about parking patterns helping improve management of urban mobility.

In 2011 the Barcelona Energy Agency drew up a second energy plan called the Energy, Climate Change and Air Quality Plan of Barcelona, which includes 108 projects to reduce energy consumption and greenhouse gas emissions and to improve air quality and energy supply systems. The plan includes implementing more renewable energy systems, increasing efficiency, and promoting transportation alternatives.

All of these measures have helped Barcelona become a leader in sustainability. Barcelona has one of the lowest per capita greenhouse gas emission levels in the industrialized world, at under 4 metric tons of emissions per person per year (Houston is at 14.1 and Paris is at 5.2). And the city is still moving forward. “In 2020 Barcelona could be a more environmentally conscious city,” according to Irma Soldevilla i Garcia of the Barcelona Energy Agency, “in which careful energy consumption will be a regular part of people’s lives.”

Image courtesy of Luciano Mortula /