Climate change

Climate change is one of the most important global problems in the 21st century. Increasing worldwide emissions of greenhouse gases such as CO2 are leading to rising temperatures which could change the environment.

Climate change

Millions at risk: defining critical climate change threats and targets [Parry, M., Arnell, N., Mcmichael, T., Nichills, R., Martens, P., Kovats, S., Livermore, M., Rosenzweig, C., Iglesias, A And Fischer, G., 2001]

To stay below 2 degrees Celsius:


  • Global GHG (Greenhouse Gas) emissions have to peak and fall in the next 10 – 15 years.
  • Global GHG emissions must fall by ~50 – 55 % below 1990 levels by 2050.

A delay of just five years matters. A delay in global action by 10 years will nearly double the reduction rates required by 2025.

EU members have agreed a 20/20/20 target, which includes a 20 % reduction in emissions (GHG), a 20 % improvement in energy efficiency, and a 20 % increase in renewable energy by 2020.

There are currently many different EU and national initiatives underway to tackle this problem. These range from efforts to replace fossil fuel energy sources with renewable energy sources, such as solar energy, to policies designed to reduce current energy usage.

Buildings have a remarkable CO2 reduction potential.
  • Buildings use 40 % of all energy
  • Space heating uses 75 % of the energy consumed in buildings

Improving energy efficiency in buildings could reduce carbon dioxide emissions by 460 million tonnes every year. This equates to:
  • Taking six million cars off the road for a total of fourteen years, or 
  • Planting a forest three times the size of France.

Comparing alternative technologies for tackling climate change, the Centre for European Policy Studies (CEPS) concludes that energy-efficient insulation in new buildings is the best way to prevent climate change whilst also improving competitiveness in Europe, and creating new job opportunities. In addition, these results are achievable with existing building practices.

The CEPS report also points out that improved energy efficiency in buildings can already be delivered using current knowhow with no new resources required for its implementation. It is also cost-efficient and poses no significant unknown risks.

The Energy Performance in Buildings Directive calls for all EU Member States to adopt a new practices for certifying the energy efficiency of buildings.

Kyoto pyramid principles:


Kyoto pyramid principle


The passive energy design of buildings reduces the energy requirements to a minimum, following a hierarchy of priorities.

1. Reducing Heat Loss
  • Additional insulation
  • Increased air-tightness
  • Effective heat recovery ventilation

2. Cost-efficient Use of Electricity
  • Energy-efficient electrical appliances and lights
  • Avoidance of unnecessary use

3. Using Solar Power
  • Positioning of buildings
  • Use collectors

4. Managing Your Consumption
  • Appropriate use and control

5. Choosing Your Energy Source
  • Heat pump
  • Biofuel 
  • District heating
  • Electricity or gas

The Kyoto Protocol is available here >>