Over the years, environmental engineers had been putting their efforts on the sustainable development over different fields such as wastewater treatment, air pollution management,energy production,ecosystem management and so forth. As the environmental problems are getting much more severe as they used to be, engineers nowadays will have to take more concern of the environmental sustainability and assess the environmental impact more carefully before they made the decisions. Apparently, a lot of things have changed for the engineers due to the environmental issues, the problems that engineers are facing today during the design process will no longer be limited to some of those general concerns.Taking the architecture as an example, the problems that architects had back to the old times were mainly focusing on the stabilization and appearance of their design, as well as the cost of materials; however, in modern world’s architecture design, our architects will not only concern about whether their designs are reliable and exquisite, but also they need to ensure that the buildings they design will do the least amount of damage to the environment. In this article, we are going to be talking about how the cleaner energy technologies in modern architectural designs have developed in the past 10 years, and also we will be talking about both the advantages and problems of applying new technologies to our modern architectural design.
The development of sustainable energy technology in architectural design
The origin of sustainable architecture can be traced back to the early 1980s, the idea was first proposed by GH Brundtland in the year 1987, it refers to a case in which architecture seeks to minimize the negative environmental impact of buildings by efficiency and moderation in the use of materials, energy, and development space and the ecosystem at large (Wikipedia contributors, Sustainable architecture).A sustainable architecture is constituted by several individual element such as sustainable energy, sustainable building materials and waste management, today we will be focusing on the importance of applying new technology into the development of sustainable energy, but let’s not forget that the other elements are equally crucial as the energy in our sustainable architecture design.
Over the last few years, environmental engineers and scientists have been strongly advocating the idea of “Zero-energy building”, which means the total amount of energy used by the building on an annual basis is roughly equal to the amount of renewable energy created on the site (Wikipedia contributors, Zero-energy building).In order to achieve the goal of zero energy consumption, the traditional methods of energy production will have to be replaced, instead of relying on absorbing energy from the non-renewable resources, taking advantage from the natural energy resources would be a better option. With the application of sustainable energy devices, the amount of energy saving can be achieved more than 30% throughout the entire energy consumption in our ordinary residential buildings.Therefore, in the last ten years, there was a huge growth of installation of renewable energy transmission devices such as wind turbines and solar panels on our newly built houses, and that’s exactly what we would love to see.
Although the renewable energy devices can help us a lot with reducing the energy consumption, it still couldn’t meet our requirement of “Zero-energy building”, there are still things that can be improved and revised. Recently, the term ” Passive Houses” has been put into the public consciousness, it might sounds like a name of a property developer, but in fact it is a architectural concept that can maximize the energy efficient in our construction design. Instead of relying on the renewable energy convert devices only, the Passive Houses are also focusing on the infrastructure and choice of materials. There are few requirements that need to be satisfied to meet the standard of building a Passive house: 1. The insulation of the building must be very effective, it’s just like when we are wearing a winter jacket, our body heat is well insulated from outside so we won’t need an extra heater to keep our body warm. 2. They must not have any air leakages in the building, so that the hot air inside of the house can be nicely kept. 3. There must not have thermal bridges inside of the house, same as air leakage, if there is any thermal bridges existing,the inside heat energy can be easily transferred to outside. 4. The building should have a proper orientation, so the sun can heat the house in the winter, and shade is provided to cool the house in the summer. 5. A heat recovery ventilation system, it can provide fresh air constantly to the house without letting any heat going out. If all the conditions above are satisfied, then the house will not need any heat or air conditioner. Under ideal condition, the percentage of energy saving of a residential house can be up to 75% -90%per year, which is pretty close to our goal of Zero-energy building.
However, without the 90% energy consumption, how could a Passive building’s energy system maintain its work? Where does the energy supply come from? Well, the energy supply for passive house can be absorbed from the solar radiant, human’s body heat, and the heat that are generated from appliances. Solar energy is the most essential energy source for the building of Passive houses, therefore all the passive houses will need to have the photovoltaic system to be installed to maximize its ability to absorb energy. Meanwhile, a heat recovery ventilation system is also required in the construction of every Passive house. Compare with the traditional ventilation system, a heat recovery ventilation system can not only export the indoor polluted air to the outside, but it can also constantly provide hot fresh air into the house by extracting the heat from the indoor polluted air and transferring those energies to the upcoming outdoor cold fresh air. With the use of high efficient energy cycling system, the emission of greenhouse gases can be effectively reduced, and also people will be able to save a lot of money. Figure below shows how the heat recovery ventilation system works in detail.
Benefits and Problems Discussion
Sustainable energy technology development is a long term project, it has benefited us in both the environmental aspect and the economical aspect. According to the statistics by FAO ( Financial Accountability Office of Ontario), during 2012 to 2014, the average household energy spending in Ontario was over 2000$ per year. Imagine if all the residential houses were built as Passive houses in Ontario, after doing a simple calculation, each family will be able to save 1500$-1800$ annually, which is a very huge amount of money.
In the aspect of environment and ecology, sustainable energy development is the key to deal with climate change. According to the United Nation Environmental Programme, buildings use about 40 % of global energy.