Mahadev Raman, president of ARUP and Princeton professor. PHOTO: Manuel Castells

"In the field of sustainability, experts cannot achieve the best results without the support of authorities, who can promote laws to encourage best practices. They must work together. This was stated at the University of Navarra by Mahadev Raman, president in America of the international consulting firm ARUP and professor at Princeton University, who taught a course at the Master's Degree in design and management Environmental Buildings (MDGAE) of the School of Architecture.

In this regard, the U.S. specialist mentioned the example of China: "Given the peculiarities of its organizational system - which has many drawbacks in other areas - it makes decisions at a high level and carries them out directly. As a result, it is making rapid progress in the field of renewable energies".

Mahadev Raman mentioned that in the USA - and similarly in Europe - 30% of CO2 emissions to the environment come from transportation, 30% from industry and 40% from construction. -and similarly in Europe, 30% of CO2 emissions to the environment come from transportation, 30% from industry and 40% from construction. With regard to the latter sector, he pointed out that the challenges do not only affect new buildings: "It is estimated that by 2050, the buildings that exist today will be half the size of those that will exist then. If we do not act to improve their sustainability, we will be in a bad status".

As a solution, he opted for the design of carbon neutral buildings, which use various systems to achieve a final balance of zero CO2 emissions into the atmosphere. He highlighted two aspects: "On the one hand, it is about reducing energy consumption needs for daily activities (heating, cooling, electricity...) and the other is the generation of renewable energy, especially with photovoltaic devices".

Smart grids in city facilities

"The first thing is to take care of passive measures, which have to do with good building orientation to maximize sunlight, natural ventilation... Then, active systems (electric lighting, air conditioning, heating...) must be designed efficiently," he said.

However, he stressed the need to consider efficiency on a larger scale than the building, as he considered that "it is not the same if the building is located in an environment with high urban density than in a area far from the city, where there is more free space. Obviously, it is easier to make a carbon-neutral building in the second case, but this environment also requires more use of vehicles due to the distances involved, which contributes to pollution".

Raman advocated the establishment of strategies at the city, provincial and state levels. Among the cases of good practices, he cited California, which in the USA is the state "with the best energy standards and which most promotes renewable energies". He added that in cities such as Boulder (Colorado), smart grids are being introduced for the city's electrical installations, so that "they can be switched on and off at the right time, thus guaranteeing improved energy efficiency".