Carsten Petersdorff 321 Introduction

In the design or building permit process, energy consumption for one year of operation of the building is typically estimated. Due to improved insulation and the subsequent reduction in energy needed for heating, the proportion of energy consumed during the building process becomes more important than by conventional buildings and should therefore also be considered. Cumulative energy demand (CED) is the entire primary energy demand over the whole life cycle of a product or a service. It is a...

Targets

Today, it is 'easily' possible to build an energy autonymous house. The problem is not technical in nature rather, it is a question of economics. The question, therefore, is how low to set the energy standard relative to the added costs that the market will tolerate. At the beginning of this interna tional research and demonstration project, some experts argued that the energy target should be relatively easy in order to facilitate a strong market penetration. Others argued that this was not...

Collector types and placement

There are many reliable and efficient collectors and types on the market today. Flat-plate collectors have been highly optimized with selective coated absorbers, low iron anti-reflective coated glazing, durable frames and gaskets, and effective back insulation. Evacuated tube collectors, with their extremely good insulation, can operate at higher temperatures with only very small heat losses. Because the losses are so small, evacuated tube collectors can deliver heat even by very low irradiance...

Introduction

Heat captured by an active solar heating system can cover a significant part of the very low energy demand of high-performance houses. Because the space heating demand of such houses is very low, the year-round energy demand for domestic hot water (DHW) becomes relatively important. An active solar system can cover a large part of this energy demand, often more than 50 per cent, since the demand also occurs in summer. The question then is if there is to be a solar system, would it not be good...

Design advice

The environmental benefits of using a biomass boiler instead of a condensing gas boiler are obvious according to results shown in this chapter. A system with a biomass boiler is to be preferred. On a yearly basis, the difference in emissions of CO2 equivalents between the two heating systems totals 930 kg. The emissions of CO2 equivalents for the solar combi-system with condensing gas burner have the same magnitude as the electrically heated building according to the conservation strategy (10.3...

Direct electric heating

Given the very minimal amount of heating needed by high-performance houses, it is tempting to consider using direct electrical heating. For space heating, base board electric heating allows individual room controls. For domestic water heating, a simple electric element is all that is needed in the storage tank. Achieving a very low primary energy consumption is, however, difficult with this solution unless a very beneficial primary energy factor for electricity is used reflecting a high...

Conclusions

A solar thermal combi-system can be a valuable component of sustainable housing. The dimensioning and economics of the system have to reflect the very low space heating demand and short heating season. For a high-performance house, a solar domestic hot water system is more easily argued than a solar combi-system, given the more constant demand for hot water over the entire year and the cost of a water-based radiant heat distribution system. If the client desires a radiant heating system, a...

Target for nonrenewable primary energy demand

The target for non-renewable energy demand is 60 kWh m2a and includes DHW and space heating, system losses and electricity for fans and pumps. This target is the same for all climates and house types. Household electricity is not included in the target since this is very much influenced by the occupants. However, energy efficient household appliances are recommended and assumed in the simulations when estimating available internal gains. Note The mean value for all cases is 57 kWh m2a. Source...

Market position

Companies striving to be a market leader (whether local, regional, national or international) must differentiate their product from that of their competitors. Leaders cannot be identified as another 'follower'. This requires a consistent marketing concept and a product that fulfils the expectations created through the marketing. Sustainable housing, until now, has been in an initial phase in the market. As it now enters into its growth phase, it is the right time for companies to define a...

Tools

Edward Prendergast, Trond Haavik and Synnove Aabrekk 6.2.1 The six-step process This process can help companies to plan business development within sustainable housing 1 Information-gathering good decision-making is based on facts, not anticipation. It is a continuing challenge to differentiate between important and unimportant information (see section 6.3). 2 Analysis based on the collected information, the position of the company relative to its competitive environment is analysed. Several...

Conserving energy

U-envelope 0.15 W m2K (walls and roof) U-windows 0.8 W m2K (average frame + glass) (triple glazing with two low-e coatings and noble gas) < 0.6 air changes per hour by 50 Pa The goal of consuming very little energy to provide superior comfort can be achieved by two basic approaches 2 use of low or non-emissions resources. An analysis of built projects demonstrates that both strategies can achieve these goals, but each has limitations. This section will examine the potential and limitations of...

The principle

Net passive solar gains occur when the solar input exceeds the heat losses of the window. Highperformance windows achieve net gains more often than conventional windows. Although the glass coatings let less solar radiation into the house (g-value), this is more than offset by the reduced heat losses. Two examples follow of energy 'book-keeping' for a sunny and an overcast day with an average outdoor temperature of 0 C. The example uses a modern conventional window, not a super window (see...

List of Acronyms and

ATS architecture towards sustainability CERT Committee on Energy Research and Technology CO2eq carbon dioxide equivalent ECBCS Energy Conservation in Buildings and Community Systems EPS expanded polystyrene insulation ERDA US Energy and Research Administration HVAC heating, ventilating and air conditioning IEA International Energy Agency ISO International Organization for Standardization LCIA life-cycle impact assessment MCDM multi-criteria decision-making OECD Organisation for Economic...

Carsten Petersdorff

In houses consuming very little energy to maintain comfort, the energy needed to build the houses represents an important part of the energy consumed over the whole life cycle of the building. Thus, it can happen that in the path to reducing energy over the house life cycle, at some point selecting a construction or component with very little embodied energy may be more effective than a measure which reduces heating energy. Another important factor to consider in selecting components is the...

Monitoring results

Monitored data from an apartment building in Freiburg, Germany, confirm the extent to which direct solar gains reduce heating peak load (Voss et al, 2004). In Figure 2.3.7, the upper straight line represents the theoretic heating peak load as a function of ambient temperature with no solar radiation, no internal gains and a constant 20 C indoor temperature. The dashed line assumes a demand reduction resulting from 2.1 W m2 of internal heat gains (100 per cent usability). The points represent...

Simulation results

Dynamic simulations of an apartment building in a temperate climate show that increasing window area need not increase heating energy demand. It may even slightly reduce demand. This can be seen in Figure 2.3.6 for the case of a top-middle apartment. This is most pronounced with the highly insulating glass in the lower curve. The extreme case is a middle mid-floor apartment. Even with the greatly reduced heating season (as a result of losses occurring from only two exterior surfaces), a...

Scope of this book

In planning very low energy housing it is useful to profit from the experience of already built projects across Europe. This book presents insights from architects, energy consultants and building physicists, as well as marketing specialists and even a banker. Three housing types are addressed apartment buildings, row houses and single family detached houses. Solutions for the housing types were optimized for three climates cold (Stockholm), temperate (Zurich) and mild (Milan). Two different...

Biomass combustion systems

This term can include anything from gas out of sewage sludge to sunflower oil to wood. The discussion here addresses only the latter. Although wood embodies only about half the energy per kg (approximately 5 kWh kg) as oil, it is appealing because it is CO2 neutral'. The CO2 from combustion originates from CO2 the tree extracted from the atmosphere. Less often stated is that wood combustion also emits fine particulates. This contributes to the serious air pollution problem that can occur in...

Maria Wall 71 Introduction

7.1.1 Solution examples by climate, house type and strategy This chapter presents example solutions for housing in cold, temperate and mild climates that achieve the targets of end energy and primary energy set by the International Energy Agency (IEA) Task 28 38. The example solutions are noteworthy in that they do not necessarily require extremes in either construction or equipment. Two design approaches are differentiated 1 conservation strategy (reducing losses) and 2 renewable energy supply...

Single family house in the Cold Climate Renewable Energy Strategy

Table 8.3.1 Targets for the single family house in the Cold Climate Renewable Energy Strategy Table 8.3.1 Targets for the single family house in the Cold Climate Renewable Energy Strategy This section presents a solution for the single family house in the cold climate. As a reference for the cold climate, the city of Stockholm is considered. The solution is focused on the use of renewable energy sources. 8.3.1 Solution 2 Renewable energy with solar combi-system and biomass or condensing gas...

Summer comfort

The following analysis on summer comfort is made for solution 1b conservation with outdoor air to water heat pump. Two ventilation strategies are tested by simulations in DEROB-LTH. The first ventilation strategy uses a bypass of the heat recovery with enforced ventilation at 1.5 ach between 7 pm and 6 am from June to August. The second ventilation strategy for achieving a good summer comfort is to bypass the heat recovery totally from April to August and to enforce night ventilation by opening...

Regional design differences

It is easiest to market a solar combi-system in regions where homeowners prefer hot water radiant heating, particularly low temperature systems. Regions where oil or wood pellet heating is preferred have proven to be good markets for combi-systems, often even large systems. Solar combi-systems have been widely sold in Germany, Austria, Switzerland, Sweden, Denmark and Norway. It seems more difficult to market combi-systems in regions where mainly direct electricity or gas is used for heating -...

Targets for space heating demand

A target was set for the space heating demand. This target ensures that the building itself will be designed with low transmission and ventilation losses. The building will not be influenced by external changes in the future, such as system changes and changes in supplied energy carriers. In addition, it is a more understandable target for occupants and building owners compared to primary energy, which is less readily understandable. The defined space heating target has been set here to be...

Main driving forces

Sustainable housing is currently finding its place in the housing market. As a result of global developments, public awareness and policy decisions, the housing industry is realizing that sustainability is an important market. Consumers begin to favour sustainable solutions for many reasons direct savings from lower energy costs experience shows potential savings as high as 75 per cent, with a payback as fast as two years for many features of such houses these saving will be greater as...

A case study Marketing new passive houses in Konstanz Rothenburg Switzerland

Edward Prendergast and Trond Haavik 6.3.1 Background A private company chose to develop a housing type unfamiliar in the Swiss housing market. Their decision process resulted in a highly successful market introduction, which can be instructive for other firms with a similar goal. At first the firm, Anliker AG, planned to build standard units for the housing estate in Konstanz. However, one of their architects, Arthur Sigg, convinced the company that a good business opportunity existed to...

Income solar gains

Four factors affecting the 'income' are meteorology glass transmittance (g) window area and how effectively (n) the 'income' is applied to reducing the 'expenses'. Meteorology (Gsol) given the very minimal heat losses, internal gains can keep the house comfortable without heating later into the autumn and starting earlier in the spring than standard houses. This reduces the heating season to the mid winter months when the days are shortest and solar radiation weakest (see Figure 2.3.5)....

The beginning of the 20th century

At the beginning of the 20th century, houses were typically not heated individual rooms were heated. The most common heat source in cities was an oil or kerosene stove. Some urban houses had the luxury of coal-fired central heating, though here, too, for reasons of economy, not all rooms were necessarily heated. At this time, however, much of the population lived in rural areas (agrarian society) and wood was the most common heating source. Hot water was heated on the stove top, or in a...

Reference buildings based on national building codes 2001

To start, common building geometries for a single family house, row house and apartment building were defined (see Appendix 1). For each country in the three climate regions, the allowable space heating demand and ventilation requirements set in the national building codes of the year 2001 were taken as the targets for the reference buildings. Working backward in an iterative process, the average envelope standards in each climate region were calculated to exactly meet the standards. In this...

Groundsurface water heat source

The seasonal storage effect of the ground at depths of 1.5 m to 2 m ensures that this heat source will be a constant temperature of approximately the average annual temperature. This greatly improves the COP of a heat pump. Source Biotech Hugler AG, www.huggler-technik.ch Figure 2.6.2 A wood pellet central heating system Source Biotech Hugler AG, www.huggler-technik.ch Figure 2.6.2 A wood pellet central heating system Figure 2.6.3 A compact heat pump-combined heating water and ventilation...

Sensitivity analysis

The following sensitivity analysis is made for solution 1b conservation with outdoor air to water heat pump. The effect of changing the orientation of the building and increasing the glazed area of the originally south-facing window is shown in Figure 8.2.8. Increasing the glazed area of the south-facing windows from 6.3 m2 to 15 m2 leads to an increase of the annual space heating demand of 6 per cent from approximately 2950 kWh to 3120 kWh. Rotating the original building by 180 degrees,...

Reducing ventilation losses

As mentioned, minimum ventilation rates are a given. Typical minimum values are 30 m3 h per occupant, which should not be reduced further and an increase of the air change rates should be anticipated over the building's lifetime. To reduce the amount of energy consumed for ventilation, the first step is to ensure that no spaces are excessively ventilated. The next step is to reduce the fan power needed to supply this required air volume. Duct lengths and layout should be optimized to reduce...

Reducing energy needed to heat domestic hot water

The amount of hot water needed is a question of individual behaviour and therefore standardized consumption values are used for planning. The most accurate values can be found in guidelines for dimensioning solar active systems. Large differences occur from one country to the other. Obviously, a key step is to specify appliances that have a minimal hot water demand. Appliances have a relatively short life span, however, so other measures are also important. Basically, two strategies are...

SWOT analysis

The SWOT factors for Anliker are summarized in Table 6.3.1, which is followed by an analysis of the different factors. Table 6.3.1 Anliker's strengths, weaknesses, opportunities and threats (SWOT) analysis Biggest company of its type within the Lucerne area Appropriate business philosophy high quality construction with low maintenance costs Willingness and a drive to be innovative and take opportunities in the market Good architecture, quality and design Whole firm behind this project Good...

Row house in the Cold Climate Renewable Energy Strategy

Table 8.5.1 Row house targets in the Cold Climate Renewable Energy Strategy Table 8.5.1 Row house targets in the Cold Climate Renewable Energy Strategy (space heating + water heating + electricity for mechanical systems) This section presents a renewable energy solution for the row houses in the cold climate. As a reference for the cold climate, the city of Stockholm is used. 8.5.1 Solution 2 Solar domestic hot water and solar-assisted heating The use of a solar combi-system and efficient...

Solar thermal system designs

If the client desires a water-based heating system, this is a good situation to argue for a solar combi-system. It provides flexibility and there are many interesting system designs on the market, varying by region and the locally used auxiliary energy sources (Weiss, 2003). The storage tank can serve both the DHW and the space heating system, and it can be heated by both the auxiliary and the solar systems, depending on conditions. The system illustrated in Figure 2.5.1 uses a wood pellet...

Single family house in the Cold Climate Conservation Strategy

This section presents two solutions for the single family house in the cold climate. As a reference for the cold climate, the city of Stockholm is used. The solutions are based on energy conservation minimizing the heat losses of the building. A balanced mechanical ventilation system with heat recovery is used to reduce the ventilation losses. Table 8.2.1 Targets for the single family house in the Cold Climate Conservation Strategy Table 8.2.1 Targets for the single family house in the Cold...

Lifecycle analysis LCA

Life-cycle analysis (LCA) is increasingly used to assess the environmental impact of buildings. As the name indicates, LCA studies the whole life cycle of a product or a process - in our case, a building -from raw material extraction, production and the use phase, to disposal and or deconstruction of the product. For the different stages of the life cycle, an inventory is made of the energy and material consumption, and of the emission into the environment. This makes it possible to identify...

Cold climate design

The example solutions for conservation and renewables in this section of Chapter 8 are compared to reference buildings, which fulfil the building codes from the year 2001 in Sweden, Norway and Finland (see Appendix 1). The examples solutions have been designed to fulfil the energy targets of this book while achieving superior comfort. The climate of Stockholm was used to represent the cold climate region. Stockholm, located at latitude 59.2 N has an average yearly temperature of 6.7 C...

Row house in the Cold Climate Conservation Strategy

Table 8.4.1 Targets for row houses in the Cold Climate Conservation Strategy Table 8.4.1 Targets for row houses in the Cold Climate Conservation Strategy (space heating + water heating + electricity for mechanical systems) This section presents a solution for the row houses in the cold climate. As a reference for the cold climate, the city of Stockholm is used. The solution is based on energy conservation minimizing the heat losses of the building. A balanced mechanical ventilation system with...

Scope

Total quality assessment (TQA) aims to provide the information necessary to design a high-performance ecological building and to confirm this performance both prior to construction and on completion of construction during commissioning. TQA does not assess architectural quality it is limited to technical issues addressing ecologically relevant aspects (i.e. energy use, CO2 emissions and water consumption) economically relevant aspects (i.e. investment costs, operational costs and external...