DOMESTIC PASSIVE SOLAR DESIGN

Domestic Passive Solar Design

Introduction3

Current/Proposed Energy Efficient Design Features4

Existing/Potential Passive Solar Design Features11

Cost Benefit Analysis For Energy Efficiency Measures16

Recommendations for other Environmentally Benign Materials17

Conclusion19

Domestic Passive Solar Design

Introduction

Buildings need to be energy efficient. Nobody doubts that. However, when it becomes the sole paradigm, unwanted consequences may be the result. Energy efficient buildings span an era of four decades now in Europe(Cole, 2008, pp:323-336). During the first decade, better insulated building enclosures were the main objective. In the second decade, passive solar took over, with architects transposing richly glazed residential designs that looked beneficial in warmer climates in terms of heating energy efficiency to the cool climate of Northwestern Europe, where the concept hardly economized on heating energy in winter; however, it confronted the inhabitants with overheating in summer(Luetzkendorf and Lorenz, 2006, pp: 334-356). That opened the market for active cooling in the residential sector, be it in a climate characterized by July mean temperatures hardly passing 17°C (62.6°F) and by cool nights compensating for warmer daytimes.

During the third decade, low energy became the new objective. The concept combined passive cooling with an up to three times lower-end energy consumption for heating (<50 kWh/[m2-a]) than average in dwellings at those days . The fact that life-cycle cost analysis classified low energy as close to optimal, meaning that over a time span of 30-40 years, total present value in terms of investment, future replacement costs, and annual cost was ±minimal, figured as a true driver behind the concept(Morgan and O'Sullivan, 2009, pp: 105-109).

The fourth decade finally saw designs such as the passive house surfacing. Basic performance is a net energy demand <15 kWh/ (m2-yr) (317 Btu/ft2). To reach that heating goal, thermal transmittance (U) of all opaque enclosure parts may not exceed 0.15W/(m2-K) (0.026 Btu/[ft2-°F-h]). Transparent parts must have a thermal transmittance <0.8 W/(m2TC) (0.14 Btu/[ft2-°F-h]) (Charron and Athienitis, 2006, pp:285-295). Thermal bridging should be minimal with linear thermal transmittances <0.01 W/(m-K) (0.0058 Btu/ [ft2-°F-h]), except at window reveals where linear thermal transmittances <0.05 W/(m-K) (0.029 Btu/[ft2-°F-h]) were imposed. A blower door test is mandatory while n50 measured should not pass 0.6 ach. The balanced ventilation system must include heat recovery with an efficiency of at least 75%. A small heat exchanger in the ventilation supply duct in series with the recovery unit typically warms the supply air to compensate for the transmission losses and the ventilation losses left(Bramleyand Power, 2009, pp: 30-48). Total annual primary energy use, including heating, domestic hot water, lighting, and plug loads, should finally stay below 120 kWh per m2 of floor area (38,010 Btu/ft2).

Current/Proposed Energy Efficient Design Features

Home energy use is responsible for over a quarter of UK carbon dioxide (CO2) emissions which contribute to climate changes. To help mitigate the effects of climate change, the Energy Saving Trust offers a range of technical solutions to help UK professionals build to higher levels of energy efficiency (Marszal et al 2011, pp: 971-979).

The development consists of a terrace of five ultralow- energy houses incorporating ...