Hefei’s Grand Theatre

Hefei’s Grand Theatre
– by Li Yirong

During the ‘Two Sessions’ of the National People’s Congress in March 2013, “Green Architecture” was pronounced to be a central issue to be addressed by the relevant departments of the Chinese government. Subsequently, mandated topics like “sustainable construction”, “eco-footprint” and “clean energy” have become commonplace in the field of architecture.

In Hefei, the capital city of Anhui Province, the 57,000m2 Hefei Grand Theatre has attracted considerable attention from the public as one of the pioneers of green architecture.

pic 1The theatre is located near the Swan Lake, to the west of Huaining Road. The massive curved roof has been likened to waves, in the original design concept. This typically literal approach to design is normal, but what is new is the solar energy system inside the roof structure.

To meet the energy-saving standard, solar panels with an area of approximately 1352 m2 have been installed to absorb solar energy, transfer it into electricity and help to maintain the temperature all-year round and save the cost of energy. Some data could prove the advantages as follow:

The solar panel system has a design life of 30 years during which time it could generate 120,000 KWH annually. Meanwhile, it is said that a total of 3425 tonnes of CO2 might be reduced per year and the amount of SO2 produced could be 11.1 tonnes less than those estimated before the construction.

Simply according to the data, the Hefei Grand Theatre solar system could be regarded as a success. The automatic system might not only save the cost of employing labour, but becomes an example of the much-vaunted green architecture construction as well.

Nevertheless, could all buildings benefit from solar energy system nowadays? Probably not. It is quite doubtful whether the policy of green architecture could be widespread, especially when we consider the various functions and locations of buildings; with varying degrees of servicing required as well as the fluctuating availability of sunlight.

Firstly, it is said that solar energy is mostly abundant in locations between 50 degree south and north to the equator, which is regarded as tropical and sub-tropical areas. With latitude of 31 degree, solar energy is abundant in Hefei and can be harnessed to meet the requirements of the Grand Theatre. In the contrast, it could be quite difficult for areas like north Europe and Russia whose position is closer to the pole to receive sufficient, regular solar energy. Furthermore, solar energy systems could be much less efficient in areas with colder climates all-year round. However, the usual efficiency might not be as high as expected or required.

pic 2Monocrystalline silicon, polycrystalline silicon and building integrated photovoltaics are the three main types of solar panels that are currently the most frequently specified for use on buildings – but these panels actually have quite a low efficiency. According to recent research, the maximum proportion of solar energy which could be converted to electrical energy by such a panel is 22% and this could only be achieved by monocrystalline silicon. However the cost of monocrystalline silicon panels is quite expensive and they are mostly applied on roofs. The other two kinds of solar panels are relatively cheaper, but their efficiency is considerably lower, only ranging from 10% to 12%. As a result, solar systems cannot be the sole source of energy.  To solve this problem, auxiliary tools like fossil fuels have to be used in some cases. It is quite fortunate for Hefei Grand Theatre that concerts and events usually take place in the evening. That is to say, most of the solar energy absorbed by the system is used at night only. However, the amount of energy required by buildings with other functions might become double or more.

Finally, one of the most important factors that might hinder the widespread use of solar energy system is the cost, especially the cost of installation. No matter, whether installing the solar system at home, or building a solar farm, the capital costs are quite high. Additionally, installing solar panels could cause large upfront fees, which requires clients effectively to agree to pay for the next few decades’ worth of power in advance. It could be another obstacle for solar promotion, particularly during a recession. This is one of the reasons that even Suntech Power Holdings, once the world’s biggest solar panel maker, is having a tough time. As a result, one megawatt hour of solar energy is estimated to cost twice as much as those conventional electricity costs.

To encourage the construction of green architecture, the Chinese government is offering considerable subsidies (even though these have recently been reduced to the solar manufacturing sector). But subsidies are nothing new. At the end of last year, the UK economy, for example, tripled its investment subsidy in green energy stating that spending on renewable energy generation will increase to 7.5billion UKP each year until 2020.

Undoubtedly, in the future, solar energy as a so-called “clean energy” source should be encouraged in practice, but it is not certain whether it is applicable or desirable everywhere. At the moment, for instance, the manufacturing capacity of China’s solar-panel industry grew tenfold – a global oversupply (or a global under-demand) – that is affecting trade relations. The Hefei Grand Theatre could be regarded as a successful example of where, and when, solar power has worked.