【作者】 牛皓；

【导师】 周集体； Peter Adriaens；

【作者基本信息】 大连理工大学 ， 环境工程， 2012， 博士

【摘要】 当前我们城市设施的压力正在不断的增大,市政设施日渐老化,迫切需要新的解决方案来加强降水管理。同时,由占有主导地位的燃煤发电厂转变为新型能源发电厂的步伐依然缓慢,从而导致了人类健康不断的接受来自污染物气体的侵害。随着乡村人口不断的涌入城市,迫切的需要加强对城市气体排放的管理以及提高市政设施能力。本论文从技术,经济,政策等角度,探索了将绿色屋顶作为一种解决城市降水以及能量排放管理方法。本文的目的是运用经济学,数学以及物理化学等模型寻求政策渠道将绿色屋顶纳为城市排放管理的一种途径。本文对华盛顿特区单个建筑物范围以及城市范围内的绿色屋顶系统环境效益进行了分析。对于单个建筑物系统,本文选择的是一个2000m2屋顶面积的商业用途的建筑物,对绿色屋顶的降水截留,建筑物节能,空气改善等环境质量进行评估；降水截留效益计算的根据是,由于使用绿色屋顶从而降低了降水管理费用,并采用两套方案进行估算,对于华盛顿特区降水管理费用为$0.33/m2/y,而对于绿色屋顶降水管理费用为在原降水管理费用的基础上降低50%,或者降低35%。对于建筑物节能效益本文采用两种方法,一种是运用美国能源部开发的软件EnergyPlus对传统屋顶和绿色屋顶的建筑物耗能情况分别进行分析,另一种为一维热通量公式法。对于改善空气质量环境效益,同样采用两种方法进行计算,一种是实验数据统计法,另一种是运用SEDUM模型计算法。而对于城市范围,本文是根据Casy Tree和Limino-tech提出的“20-20-20”绿化措施对绿色屋顶的降水截留,对市政基建设施需求减少,建筑物节能,污染物减排,对空调系统需求减少,净化空气等环境效益进行分析。在城市系统中,建筑物节能效益采用EnergyPlus方法进行计算。C02,NOX, SO2减排效益是根据绿色屋顶建筑物用电、天然气使用的减少同电力部门和取暖部门污染物排放因子的乘积得到的,空调系统环境效益也采用两套方案。最后改善空气质量环境效益同样采用实验数据统计与SEDUM模型计算两种方法。结果发现对于华盛顿特区一个2000m2的商业建筑物绿色屋顶,每年降水截留的环境效益为232-332美元,建筑物节能效益为每年708-2500美元,改善空气质量环境效益为每年255-3445美元。对于华盛顿城市范围“20-20-20”绿化措施下的绿色屋顶降水管理费用降低环境效益为每年22-32万美元,雨水处理费用减少的环境效益约为每年95万美元,基建设施需求减少的环境效益为每年8万美元。建筑物节能效益为每年87万美元,气体污染物减排效益为每年9-41万美元,对空调设施需求减少的效益为每年2-4万美元。空气改善环境效益为每年24-327万美元。最后将这些环境效益输入到净现值分析模型的当中,对40年期间,华盛顿特区的绿色屋顶和传统屋顶费用进行分析对比。结果显示,对于华盛顿特区单个建筑物系统,绿色屋顶的净现值比传统屋顶的净现值要低25-39%,这主要归功于节能效益。对于华盛顿城市系统,绿色屋顶净现值比传统屋顶净现值要低30-41%,在所有的环境效益当中,主要是也是归功于建筑物节能效益。在整个城市系统范围内,绿色屋顶的投资回报期为7-21年。同时,本文还对华盛顿绿色屋顶系统的净现值进行了不确定值以及灵敏度分析,结果发现,在一般情况下(没有CO2总量控制与交易制度的政策法规条件下),绿色屋顶的最快投资回报率可缩短1-2年,在所有的环境效益参数中影响净现值的主要因素是商业用电费用(平均为2.1±1.1%),民用天然气价格(平均为1.9±1.4%),CO2市场交易值(平均为0.7±0.4%)。在CO2总量控制与交易制度的政策法规条件下,绿色屋顶的最快投资回报率可缩短将近4-5年,如此短的投资回报率在所有的环境效益参数中的主要影响因素是CO2税值(平均为4.8±3.7%或2.2±0.7%),其次是商业用电价格。最后,本文将对华盛顿特区城市系统绿色屋顶环境效益分析所建立的方法应用于温哥华市,并对温哥华市的绿色屋顶在城市范围内进行计算。同样是根据降水截留,建筑物节能,改善空气质量的环境效益方法进行分析。温哥华市,主要侧重于降水截留效益的分析。其中包括降水管理费用的降低,改善水体质量的环境效益,降低市政设施发展费用的效益,降低由于气候变化带来的潜在危险的环境效益,降低降水给鱼类栖息地带来危险的环境效益,降低降水对市政设施腐蚀的环境效益。其中改善水体质量环境效益分析也采用两套方案。最后同样将这些环境效益输入到净现值分析模型当中以确定绿色屋顶的投资回报率。结果发现温哥华市绿色屋顶总的降水截留效益为每年436-562万美元,总的建筑物节能环境效益为每年269-311万美元,空气质量改善环境效益为每年254-2124万美元。温哥华市40年后绿色屋顶的净现值比传统屋顶低了28-48%,投资回报率为6-21年,在所有的环境效益中,总的降水截留环境效益对温哥华市绿色屋顶影响最大。目前降水截留,节能,空气质量净化等效益的分析表明,只要将这些环境效益考虑进去,在市场为基础的激励政策下是可以降低绿色屋顶和传统屋顶之间的价格差距的。本研究足以证明绿色屋顶可以作为可得到的最佳控制污染技术,然而,当前市场为基础的激励政策还不足以促使这项绿色技术的推广。更多还原

【Abstract】 Our urban infrastructure systems are stressed. The decay of water infrastructure is spurring demand for innovative solutions for stormwater management. Concurrently, the transition of predominantly coal-based utilities to renewable portfolios is slow, resulting in continuing adverse health impacts from air pollution. The need for emissions management and resilient water infrastructure in cities will further increase as the world’s population continues to move to urban centers.This dissertation explores the technical, economic, and policy opportunities for vegetated roofs as one solution to stormwater and energy emissions management. The objective was to explore policy strategies to integrate green roofs into emissions management using quantitative economic and physical-chemical modeling tools.This dissertation quantifies the green roofs benefits for Washington DC both at building-specific and city scale. For building-specific scale, we evaluate stormwater benefits, Energy savings and air quality improvement benefits for a2000m2roof area commercial building. For stormwater benefits, we consider two scenarios:$0.33/m2/y,50%off;＄0.33/m2/y,35%off. We also use two methods, EnergyPlus developed by US DOE and1-D heat flux equation, for estimating green roofs energy savings.For air quality improvement benefits, also two estimate methods for testing, experimental data statisitics and SEDUM model calculation.While we made assessment for green roofs benefits, including stormwater fee-based benefits, stormwater operational benefits, stormwater size reduction benefits, energy fee-based benefits, avoided emission benefits, air conditioner size reduction benefits,and air quality improvement for Washington DC at city-scale based on’20-20-20’plan proposed by Casy Tree and Limino-tech. Energy fee-based benefits were evaluated by EnergyPlus model. CO2, NOx, SO2avoided emission benefits were calculated by reductions in electricity and natural gas associated with their emission factors in power plants and space-heating equipment sectors. Scaled energy infrastructure benefits were calculated using two size reductions methods for air conditioners. Lastly, the air quality improvement benefits were also calculated based on two estimate methods, experimental data statisitics and SEDUM model calculation.The results showed the stormwater benefits are＄232-332/y, energy savings were$708-2500/y, and the air quality benefits are＄255-3445/y for2000m2green roof on a commercial building in Washington DC. While for the city-scale, the stormwater fee-based benefits are estimated at＄0.22-0.32M/y, the operational savings are＄0.95M/y, the infrastructure size reduction benefits are＄0.08M/y, energy fee-based savings are＄0.87M/y, however, the avoided emission benefits are＄0.09-0.41M/y, the air conditioner size reduction benefits are＄0.02-0.04M/y, and the air quality improvement benefits are estimated at$0.24-3.27M/y for Washington DC.Lastly, all these benefits are integrated into an economic framework model net present value (NPV) to compare the cost of conventional roof to green roof. The results indicated that the40-year NPV of green roofs is25to39percent less than that of conventional roofs at building-specific scale mainly due to energy savings during all the benefits for Washington DC. For Washington DC city-scale, the40-year NPV of green roofs is30to41percent less than that of conventional roofs also mainly due to energy savings during all the benefits for Washington DC.The results also illustrated the breakeven of green roofs NPV are7-21years for Washington DC.Also uncertainty and sensitivity analysis is conducted for green roof system in Washington DC. The model estimated that green roofs NPV break even are decreased by1-2year by these uncertainty energy-relative prices without CO2cap-and-trade system. The main driver for the shorter break even is the commercial electricity prices (mean value:2.1±1.1%), followed by residential natural gas prices (mean value:1.9±1.4%), and CO2prices (mean value:0.7±0.4%). While the model estimates show that cap and trade induced price increases have the potential to decrease the NPV break even of green roofs by4-5years. The main driver for the shorter break even is the CO2allowance valuation (mean value:4.8±3.7%and2.2±0.7%), followed by commercial electricity prices.Finally, we implement the established green roofs benefits evaluation methods based on Washington DC system to City of Vancouver.We evaluate stormwater benefits, energy savings, and air quality improvement benefits for green roofs system for City of Vancouver, and more focused on stormwater benefits, including stormwater fee-based benefits, receiving water quality improvements benefits, Reduction in major storm flows benefits (DCC), reduction in risks due to climate change benefits, reducing storm water impact to aquatic habitat benefits, reduction of receiving stream erosion benefits. The receiving water quality benefits are estimated based on two scenarios. Then all these benefits are incorporated inot NPV model to determine the break even of green roofs.The results indicated the total stormwater benefits are＄4.36-5.62M/y, the total energy savings are＄2.69-3.11M/y, and the total air quality improvement benefits are＄2.54-21.24M/y for green roofs for City of Vancouver at city-scale.The40-year NPV of green roofs is28to48percent less than that of conventional roofs mainly due to total stormwater benefits during all these benefits.The break even of green roofs are found to be6-21years for City of Vancouver.Analysis of current stormwater, energy savings and air quality policies showed that market-based incentives can close the cost differential once both stormwater and air quality incentives are considered. This work is sufficiently robust to demonstrate the economic and emissions mitigation potential to be included in best available control technology (BACT) consideration. Yet, market-based policy incentives are currently insufficient for widespread adoption.更多还原