"We are building energy-saving, focused only on the individual building energy-saving technology and environmentally-friendly energy applications, but ignores the extent and the whole city of regional energy applications, water, electricity, gas and other departments administer, resulting in energy recycling inefficiencies, this is the current city of soft ribs. "Last week held in Nanjing, China building regional energy planning seminar experts speak out cities shall have special energy-use planning and building a low carbon, livable city.
Relative to a single regional energy-saving, high efficiency of energy use
ASC Hsu made presentations, regional energy is an area in the heating, cooling, electricity and resolve regional energy demand of energy systems and integration.
Hsu Wen Fa said that technological development has energy to be able to use the "four steps, such as" gas-steam combined power generation — cchp-a heat pump regional energy system, first with natural gas in gas turbine combustion temperatures promote the turbines in the power generation, generation of exhaust gas-temperature to + 500-600 degrees into the waste heat boiler produces steam, then fed into the steam turbine power generation, after finished electrical steam heat exchanger cooling, heating, and finally with the heat pump to heat lifting condensation water, used for heating or hot water production. This way of recycling, gas heat almost been "discarded exhaustion", provided that the regional plan for refrigeration, heating, hot water is "down home" by converting equipment, transmission and distribution network with public and civil construction.
Experts, relative to a single energy saving measures, regional energy use more efficient. For example, the city's summer air conditioning electricity has become rigid load, increasing electricity generation capacity and size of grid construction, resulting in increased electricity costs, and on the other hand, many to civil heating-dominated power plant at idle, as by refrigeration technology to cogeneration to cogenerated through transmission and distribution system connecting cities users, having built so many peak power plant.
Regional energy utilization maximized, urban planning is the key
Experts in statistics, China's 287 prefecture-level city in China's energy consumption is accounted for 55 per cent of total energy consumption, CO2 emissions account for nearly 59 per cent, as all the cities and towns plus, to account for social total energy consumption by 80 percent.
Green building technology centre in King cloud, China city building every year to 20 billion cubic meters of annually, a sharp increase in energy consumption, while at the same time, existing planning system still does not solve the problem of urban energy systems, water supply, heating, gas, electric power these four special planning between the lack of coordination, redundancy, inefficient. In fact, for the same building cold, heat, gas and electricity needs, you can choose between different energy sources, such as hot water load through the gas, electricity, solar water heater, heat pump and heat supply network, etc., building heating and air conditioning are also available through coal, gas, electric power, oil and other energy sources and conversion equipment to achieve, not "self-built a, self-contained".
Experts believe that if the architecture as a micro-technology energy-saving of "hard" to urban areas, building group energy planning is a macroeconomic sense of "soft energy saving". Urban planning to make energy demand and supply in construction development time and manpower utilization, and avoid the energy transmission and distribution sector mutual "fight", "energy" internal friction.
The lack of "thermal environment planning" necessarily aggravate the "heat island effect"
Increasing the "heat island effect," is the city's other energy black hole. Experts believe that this margin of the current urban planning rarely consider "the effect of thermal environment".
The "heat island effect" is the largest city in the observed temperature higher than the same period in the surrounding rural environment temperature of a phenomenon. Experts on Tianjin's research has shown that the Centre districts of heat island 1 degree Celsius, each increase of air conditioning load increase 15 percent, increase the frequency of air conditioning use further worsening the urban thermal environment.
Residential construction Ministry science and technology promotion center Zhang ling, experts believe that too high a volume rate cause the urban unit area to absorb solar radiation of the building surface area increases, improved urban center of air temperature, and high-rise buildings open to the sky view factor is too small, lower wind speed, causing the heat at night.
Experts noted that mitigate the heat island effect also in urban planning, urban development on the one hand, to avoid spreading pie-style high intensity development, lower downtown building density, height, volume rate, on the one hand through greening, River City "of isolation reduces surface temperature". In addition, to building surfaces painted white, light-coloured, reflective coatings, reduce solar radiation, select heat coefficient smaller external wall insulation, can also play the role of "natural air conditioning".
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