The IEA has projected that a cumulative $44 trillion in investment will be needed in the global energy supply over the next 15 years. Another $23 trillion will be required for energy efficiency improvements. Worldwide 40% of energy is consumed by buildings. In the U.S. 70 % of electric power goes to buildings. Measures aimed at improving the efficiency of buildings have been introduced in Europe, the U.S., Japan and other jurisdictions.
Zero energy buildings are loosely defined as buildings that generate as much energy as they consume. But there is as yet no single standards body defining what a zero energy building is. Different countries and even within the same country different bodies define zero energy buildings in different ways. According to a new report from Navigant Research, global zero energy building revenue is projected to grow from less than $100 billion in 2016 to $1.4 trillion by 2035.
Nearly zero energy buildings in the E.U.
The European Union (EU) has taken a leading role in focussing energy conservation efforts on the energy efficiency of buildings. The EU has mandatory carbon emission reduction standards, referred to as the 20-20-20 standard, which among other things requires the EU to improve energy efficiency by 20% by 2020. Another important objective is reducing its dependence on imported energy, which currently accounts for half of EU energy usage. In 2002 the European Commission promulgated the Energy Performance of Buildings Directive (EPBD) which requires all EU member states to upgrade their building regulations and to introduce energy certification schemes for buildings. About a year ago the European Commission (EC) proposed a new Energy Efficiency Directive (EED) , also known as the EPBD recast, which imposes a legal obligation for all member states to establish energy saving schemes, with the public sector leading by example.
Energy efficiency is especially critical for Germany which not only needs to comply with the 20-20-20 standard, but also to find energy sources to replace its (non-emitting) nuclear power plants that are scheduled to be closed by 2022. In Germany buildings currently account for 40 percent of power consumption and a third of CO2 emissions. The German 40 year master plan calls for aggressive energy efficiency policies including new insulation standards and for all buildings in Germany to be refurbished in line with the new insulation standards by 2050, reducing energy requirements for heating by 20 percent by 2020 and by 80 percent by 2050, and providing tax relief on energy taxes to companies contributing to energy savings.
A major area of focus in the EU is “nearly zero energy” buildings. A nearly zero energy building on average over a year generates as much energy from renewable energy sources as it consumes. For new buildings, the EPBD recast fixes 2020/2021 as the deadline for all new buildings to be designed to be nearly zero energy. For public buildings the deadline is even sooner, by 2018/2019.
Zero emissions buildings in Japan
Japan‘s announced mid-term emission reduction target is to cut Japan's GHG emissions by 25% by 2020 compared with 1990, subject to international negotiations. But Japan has said that it plans to revise this target in light of the Fukushima accident and presumably in light of the decision to shut down its nuclear power plants by 2040. According to an analysis by the Ministry of Economy, Trade and Industry (METI), the largest reduction will need to be realized in commercial sector, by about 27%. Residential/commercial-sector accounts for 30% or more of final energy consumption and has increased remarkably compared to the industrial and transportation sectors. Energy saving measures for commercial buildings are urgently required, since the commercial sector including office buildings consumes more than half of total energy consumption in the residential/commercial sector. Moreover its growth has been more striking than that of the residential sector.
The Government of Japan put forward its "zero emissions buildings" target in April, 2009. It defines a zero emissions building (ZEB) as one that has net zero CO2 emissions on an annual basis through energy efficiency and renewable energy generation on-site. The announced objective ia that all new public buildings will be zero emissions by 2030.
Zero net energy buildings in the U.S.
The U.S. Energy Independence and Security Act of 2007 (EISA 2007) requires that by 2030 all new Federal facilities must be "zero net energy" (ZNE) buildings. On October 19, 2007, the California Public Utilities Commission (CPUC) adopted aggressive targets for ZNE
- All new residential construction in California will be zero net energy by 2020
- All new commercial construction in California will be zero net energy by 2030
- 50% of existing commercial buildings will be retrofit to ZNE by 2030.
According to the New Buildings Institute (NBI) there are 332 ZNE (zero net energy) verified and emerging commercial and multifamily buildings in the U.S. and Canada. The ZNE buildings on this list have either achieved or committed to the goal of producing as much renewable energy onsite as they consume over the course of a year.