【“绿城”弗莱堡的烦恼（上）】 弗莱堡

　　德国的弗莱堡被认为是欧洲的环保样板城。这里排斥汽车，房顶上铺满太阳能电池板，孩子们上的是“森林幼儿园”，即使下雨下雪冷到零下十五度，也必须在户外玩够三个半小时，以便“亲近自然”。极端环保主义不仅受到外界质疑，在当地的居民中也引起了争议。
　　
　　It is 6℃ outside, and a 1)dusting of snow can be seen on the Schauinsland―the low hill overlooking 2)Freiburg, where the 3)burghers of the southwest German city take their children hiking. In Meinhard Hansen’s apartment, however, it is perpetual summer; the sun streams in through tall, south-facing windows and a 4)gauge on the wall reads “24℃”. Next to it, the words “Heizung 0” appear in a small glass window. “Heating, zero,” Meinhard translates. “In fact, we haven’t switched the heating on for weeks.”
　　While a typical home in Germany 5)squanders 220 kilowatt hours of energy a year for each square metre of 6)floor space, this one wastes 15kWh/m2 a year. “My mother-in-law has an old house in the country,” says Meinhard, “and she uses 6,000 litres of oil a year to heat it. We use 150 litres.” On one wall there is a radiator, but it is stone cold. “It’s just for psychological reasons,” he says, “because my wife never believed this was possible.”
　　The impossible dream was a “passive house” where no active system is needed to maintain a comfortable temperature. Super-insulated with foam and 7)lagging up to 30cm thick, the flat is triple-8)glazed and externally sealed. Fresh air enters at ceiling level and is sucked out through a funnel on one wall. “The heat from the warm air going out is transferred to the cold air coming in,” says Meinhard, Freiburg’s chief architect and a world authority on passive houses. So far, his company has built about 100.
　　Opening a cupboard, he shows me how the cold and warm 9)ducts meet in a knot of 10)corrugated silver piping. The result? An almost constant
　　temperature without the need for heating―because warmth is provided by cooking, lighting, even warm-blooded mammals. “My wife and I produce 100W of energy each, the dog another 20W,” says Meinhard, bending down to check the animal is still breathing. “If we hold a dinner party, we have to open the windows.” By his calculation, the entire flat could be heated with 30 candles.
　　In Freiburg, passive houses like this are relatively few, but energy-saving houses are the norm. Elsewhere in Germany, the law states that every new house built must waste no more than 75kWh/m2 per year but the specification in Freiburg is radically lower. “It used to be 65kWh per year,” says Meinhard, “but we are now discussing a new Freiburg law of 55, 50 or even 40kWh.”
　　It is part of Freiburg’s unrelenting quest to be one of the greenest cities in the world, helped by the (uncomfortable) fact that it was flattened by bombers in the Second World War and rebuilt on enlightened, energy-saving principles.
　　“We always compete to be the most ecological town,” says Claudia Duppe, a lecturer and resident of Freiburg’s Rieselfeld quarter, “whether it is the length of the cycle paths, the number of people cycling to work, or the amount of solar panels on the roofs.” Over a glass of local wine, she tells me about her life. As well as living in a passive house, she cycles everywhere (“the cycle routes are brilliant”) or takes the 11)tram―a cheap, fast mode of transport that makes car
本文为全文原貌 未安装PDF浏览器用户请先下载安装 原版全文 　　ownership unnecessary. “We don’t own one,” Claudia says, “but we paid �00 to join a car-sharing club.” She only hires a car for “big loads” when shopping, or “to go skiing in the mountains.”
　　Like all good Germans, Claudia recycles―and her food waste is collected for 12)composting. With her partner Thomas Beyer, a physicist, she has chosen the greenest
　　education possible for her two-year-old daughter, Helen. “She goes to a forest kindergarten a short cycle ride from here,” says Claudia. “The children play outdoors for three-and-a-half hours a day―whether it is rain, hail or snow. When Helen started in November, it was -15℃.”
　　I ask how Helen benefits from such a hardy education. “It’s a different way of playing,” says Claudia, “They forbid any toys, so the children play with sticks and leaves. Each day, they take what the forest offers. By now, lots of things are in bloom; they can open tiny, brown-13)crusted buds and there is something green inside. They slow down, they are themselves, they live with the cycle of nature ...”
　　It sounds extreme, but Rieselfeld is a fairly extreme place. I take a tour with Andreas Roessler who has lived here since the pioneering days of 1996.
　　“Rents were too high in the Nineties,” he explains, “and we had a lot of trouble getting families into affordable housing.” Public money for social housing had dried up, and the city of Freiburg was selling off plots of land to groups of families (anything from 6 to 16 parties) so they could employ an architect and build their own block of flats―a way of splitting the cost of ownership and making property affordable. Roughly 40 percent of homes in the district are privately owned and self-built like this, while 40 percent are rented. The remaining 20 percent is social housing funded by private investors―a deliberate formula intended to create a healthy social and economic mix.
　　It’s a brave utopian vision. Its housing blocks are built to a uniform height (usually four storeys). Because the properties are all the same age, the place lacks character and charm. In his offices at the Technisches 14)Rathaus on the other side of town, Wulf Daseking, Freiburg’s chief planner, agrees that Rieselfeld is ugly. “It was the first pro-ject, the first test.” What he means is that Riesel-feld was the first new area built from scratch after his appointment in 1984. The other was Vauban, the radical car-free quarter carved from an old French army base in 1998.
　　
　　户外温度只有6摄氏度，绍因斯兰德山上还留着薄薄一层积雪――这座低矮的山岗俯瞰着德国西南部的弗莱堡城，当地人常带着孩子们来登山远足。然而在梅哈德•汉森的家里，一年四季都像是夏天。太阳光穿过高高的南向窗户一泻而入，挂在墙上的温度计显示屋内温度为24摄氏度。在温度计旁边一个小小的玻璃视孔上，显示着“Heizung 0”的字样。“制暖，零度。”梅哈德翻译给我听，“事实上，我们已经好几周没有开制暖键了。”
　　一般来说，一栋德国的典型住宅每平方米楼面面积每年要耗费220千瓦时的能源，但是梅哈德的这栋房子每平方米每年只耗费15千瓦时。“我岳母在乡下有个老房子。”梅哈德说，“为了供暖，每年要用6000升燃油，而我们只用150升。”在一面墙上装着暖气片，但我摸了摸，发现它像石头一样冰凉。“那只是个心理安慰。”梅哈德说道，“因为我妻子总觉得我们不可能这样经济地实现供暖。”
　　这个“不可能的梦想”就是“被动式建筑”――它的构造不含有任何用以维持舒适温度的制动系统。这种建筑铺设了厚达30厘米的泡沫来隔热，装了3层玻璃，把套间封得严严实实。新鲜空气从天花板的高度进入，通过一面墙上的通风管道抽出。“往外去的温暖气体中的热量正好转移到了进来的冷空气里。”梅哈德说。他是弗莱堡的总建筑师，世界首屈一指的“被动建筑”设计权威。到目前为止，他的公司已经建造了大约100栋此类建筑。
本文为全文原貌 未安装PDF浏览器用户请先下载安装 原版全文 　　他打开一个橱柜，向我展示冷暖两股空气的传送管道是如何在皱缩成波纹状的银色管道交结处汇合的。这样设计的结果就是，不需要人为制暖，室内就可以保持几近恒定的温度――因为烹饪、照明，乃至温血的哺乳动物都能产生热量。“我和妻子每人产出100瓦的热量，我们的狗也可以产出20瓦。”梅哈德边说边俯下身摸了摸狗的鼻子，以确认它还在呼吸。“如果我们在家办晚宴的话，就非得开窗散热不可了。”据他估算，只用30根蜡烛，就可以使整间公寓升温。
　　在弗莱堡，像梅哈德家这样的被动式房屋相对较少，但是节能建筑已是当地社会的主流。在德国其他地方，法律均规定每栋新建房屋的能耗每年不能超过每平方米75千瓦时，但是在弗莱堡，当地人自己规定的标准严苛得多。“过去我们要求每年的能耗不得超过每平方米65千瓦时。”梅哈德说，“但是现在弗莱堡又开始讨论一项新的法案，希望每年每平方米的能耗不要超过55、50，甚至是40千瓦时。”
　　弗莱堡永不停歇的诉求之一是希望能够成为世界上最“绿色”的城市之一。弗莱堡在第二次世界大战期间曾有惨痛的经历，整个城市被炸弹夷为平地，但此事却正好让它能全新开始，完全按照节能原则进行重建。
　　“我们一直在竞争成为最生态的城市。”弗莱堡市著名生态小区瑞斯菲德的居民、讲师克劳迪娅•杜普说，“不管是从自行车道的长度、骑自行车上班的人数，还是屋顶太阳能电池板的数量来讲，我们都很有实力。”喝完一杯当地出产的葡萄酒的功夫，她向我讲述了她的生活。她和梅哈德一样住在被动式房屋里，出门不是骑自行车（“自行车道的路线设计得太棒了”），便是搭乘有轨电车――这种便宜、快捷的交通工具，令私家车变成可有可无之物。“我们没有私家车。”克劳迪娅说，“不过我们交600欧元参加了一个拼车社团。”她只是在有“大宗货物”要运送时才租辆车用――比如购物，或者“去山区滑雪”。
　　和所有善良正派的德国人一样，克劳迪娅崇尚变废为宝、回收再利用的生活方式，她把自家的食物垃圾都收集起来，用于积肥。她和自己的伴侣、物理学家托马
　　斯•贝尔一起，为两岁的女儿海伦选择了可能最具环保意识的教育方式。“她在附近一个森林幼儿园上学，骑车过去很近。”克劳迪娅说，“孩子们每天在户外玩三个半小时，不管下雨、下冰雹还是下雪。海伦是11月份入学的，当时气温是零下十五度。”
　　我问她海伦从这样一种艰苦的教育中获得了什么益处。“那是一种与众不同的玩耍方式。”克劳迪娅说道，“他们禁用任何玩具，这样孩子们只能玩树枝和叶子。每天，他们都在享用森林的馈赠。现在这个时候，很多草木开始发芽。他们可以打开小小的、有褐色外皮的蓓蕾，看见里面有绿色的新生命。他们的生活节奏放慢了，回归自我，随着大自然的更替嬗变而成长……”
　　这听上去颇为极端，但是瑞斯菲德确实是一个相当极端的地方。安德里亚斯•罗斯勒从1996年起就住在这儿，当时，此地还处于建房实验的先锋期。他带我在附近转了一圈。
　　“上世纪90年代时的租金太高了。”他解释说，“我们无法建造出大多数家庭都能负担得起的房子。”建社区住宅的公用基金也空了，弗莱堡市只好将土地分成小片，出售给一个个由6－16户人家组成的集体，让他们可以自己雇建筑师建造公寓楼――这样可以分摊成本，让人们能支付得起房产的费用。在这一带，差不多40%的房子都是这种自建的私人物业，还有40%是用于租赁。其余20%则是由私人投资商开发的社区住宅――这种比例是事先特意安排好的，目的是创建一个健康的社会和经济混合体。
　　这是一个勇敢的、乌托邦式的念头。这里的房子一律等高，通常为四层楼。因为楼龄全部一样，所以整个地方的建筑缺乏特色和魅力。沃尔夫•达斯肯是弗莱堡的总设计师，他的办公室位于弗莱堡市另一边的科技议会厅。他向我承认，瑞斯菲德确实难看。“这只是计划的第一步，是最初的实验。”他的意思是说，瑞斯菲德是他1984年到任之后从无到有建设起来的首个新居民区。另外一个小区是弗本，1998年由一个旧的法国军事基地改造而来，是个彻底的无汽车小区。
　　
　　
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