tag:blogger.com,1999:blog-539282911735603328.post7307065478136364603..comments2022-09-24T03:07:13.371-07:00Comments on DecPassive: Passive House Case Study Hannover-Kronsberg, GermanyDecPassivehttp://www.blogger.com/profile/00840856751165618530noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-539282911735603328.post-55668674054046616212011-03-16T07:35:41.993-07:002011-03-16T07:35:41.993-07:00In reply to the third comment by Sean,
Yes Sean t...In reply to the third comment by Sean,<br /><br />Yes Sean that actually caused variations in temperatures of neighbouring houses which lead to increased energy consumption of the house with the higher set temperature as the difference in temperature results in heat flow through the partition wall from one house to its neighbour. This lead to a reduction in one of the houses energy consumption but an increase in energy consumption in the other house. To explain this better consider that neighbour A has set his room temperature at 23°, whereas neighbour B has set his at 19°C. The resulting heat flow through the partition wall from A to B in a Passive House standard terraced house is almost 900 kWh/a. House B’s heating consumption is thus reduced by about 7,6 kWh/(m²a), whilst house A’s consumption is increased by the same amount. The heat has not been lost, it is just in the neighbour’s house. The absolute level of this effect is not dramatic; the effect is economically compensated due to the only partially consumption-dependent billing.DecPassivehttps://www.blogger.com/profile/00840856751165618530noreply@blogger.comtag:blogger.com,1999:blog-539282911735603328.post-16931609232472017902011-03-15T14:33:06.939-07:002011-03-15T14:33:06.939-07:00In reply to the second comment by David
The heati...In reply to the second comment by David<br /><br />The heating for the hot water is supplied by the solar thermal system. The solar thermal system consists of a ca. 4 m² flat collector field on the southern roof, a control unit, the expansion vessel as well as the heat exchanger in the lower part of the hot water tank. It functions as an independent system with an anti-freeze liquid filled closed circuit. Under sufficient solar radiation, the control unit activates the pump. Due to the placement of the heat exchanger in the lower part of the water tank, it can be completely heated from below (300-litres). The storage tank temperature sensor is mounted in the area of the solar heat exchanger. The second temperature sensor is located in the collector on the roof. The temperature in the storage tank can be heated up to roughly 85 °C by solar energy. The above mentioned water mixer makes sure, through the mixing of cold water, that no scalding occurs at the taps.<br /><br />In reply to your second question.<br /><br />The houses were monitored over a period of time. In regards to thermal comfort the houses only saw a slight deviation in room temperature with an average of 21,1°C in the middle of the winter and very slight deviation (20,9°C) on the coldest day which shows that comfort is guaranteed, independent of the climate conditions in these passive houses. In summer time the room temperatures deviated between 25°C and 25,7°C on the hottest day of the year.<br />In regards heating load the passive house measured between 8,8 W/m² the first year and 7,0 W/m² in the second year which is well below the required value of 10 W/m² therefore the passive house proved successful in this regard.<br />In relation to heating consumption the houses measured at 16,0 kWh/(m²a) in the first year which is slightly above the required 15 kWh/(m²a) but in the second year the energy consumption was reduced to 13,3 kWh/(m²a) which is below the required value. Overall the houses have lived up to the expectations of passive house constructionDecPassivehttps://www.blogger.com/profile/00840856751165618530noreply@blogger.comtag:blogger.com,1999:blog-539282911735603328.post-12603811467430590232011-03-15T13:53:49.057-07:002011-03-15T13:53:49.057-07:00In reply to the first comment by EGG
Well Egg the...In reply to the first comment by EGG<br /><br />Well Egg the reason that the houses appear so close together is that they are actualy terraced houses as stated at the start of the blog. As you can see from the aerial photograph the shawdows cast are not interferring with the solar gain of the buildings. The terraced block of passive houses are facing south west to maximise solar gain and the two blocks of housing are too far apart to cause any over shading.DecPassivehttps://www.blogger.com/profile/00840856751165618530noreply@blogger.comtag:blogger.com,1999:blog-539282911735603328.post-77951188304659054462011-03-09T11:46:44.060-08:002011-03-09T11:46:44.060-08:00Hello Dec, Were there any considerations to be mad...Hello Dec, Were there any considerations to be made for the fact that the thermal envelope extends to the row of houses and not each house unit from the point of view of airtightness and insulation. For example if a neighbouring house is unoccupied for any reason the windows could be left open, or the lack of heating when unoccupied could cause an increased heat load on the adjacent units if there isnt sufficient insulation in the party walls. I imagine that the thermal difference would still be minimal enough not to cause issues but I wonder if this was looked into at all.ssirr_passivehttps://www.blogger.com/profile/03132263525858503137noreply@blogger.comtag:blogger.com,1999:blog-539282911735603328.post-65903449123738159472011-03-09T11:20:19.338-08:002011-03-09T11:20:19.338-08:00Hey Dec.
This is a very interesting development b...Hey Dec. <br />This is a very interesting development because it demonstrates the use of the Passive House standard on a large scale. Developments such as give us an insight to what public housing in the future may look like. Also this development shows up how far ahead Germany is in terms of Passive House development, due to the fact that this project was completed in 1998.<br />Just some questions...<br />1. How is heating for hot water provided ?<br />2. Seen as this development has been in use since 1998, it should be a strong testament to the quality of the Passive House standard. Are the houses performing as they should and have any design flaws been realised ?David Hanevyhttps://www.blogger.com/profile/07912606855886090791noreply@blogger.comtag:blogger.com,1999:blog-539282911735603328.post-12807799114655904112011-03-09T11:18:18.716-08:002011-03-09T11:18:18.716-08:00Dec, good blog well done. I was just wondering did...Dec, good blog well done. I was just wondering did you come across if any of the houses suffer from any over-shading as they appear to be close enough together from the photo above??Egghttps://www.blogger.com/profile/04658602102235308092noreply@blogger.com