With energy costs skyrocketing, we are all looking for ways to reduce our power consumption. By using more energy efficient light bulbs, to enhance seals around windows and doors, there are numerous approaches and various strategies which can be employed to decrease energy use and save money. However, as with most things beginning with a correctly designed system to begin with supplies different advantages.
In this case, a house designed with solar passive design principles is your best starting point. These design principles utilise”passive design” facets to maximise thermal comfort, i.e. they use the climate and neighborhood environment, such as the sun and natural breezes, to reduce the need for artificial heating and coolingsystem. In Australia, these costs can account for roughly 40% of energy prices in the average home, but might account for even more in various other climates.
Homes built from the northern hemisphere ought to be oriented such that their long axis is aligned east/west, with bigger windows at the walls to boost solar heating during the colder months. If possible during the design stage, these windows should not be obstructed from sunlight by such items as other trees, buildings or other structures between the hours of 9am to 3pm allowing sunlight to stream in.
In the warmer months, once the sun is higher in the sky, it’s important to restrict the amount of sunlight going into the home using things like eaves, awnings, natural shade from trees etc.drapes, blinds or shutters.
Note; for houses in the southern hemisphere, the situation is reversed and the key windows should be located in north-facing walls.
Another component to solar heating is thermal mass. Things like cavity brick walls, concrete floors and internal brick walls all add thermal mass to a home.
From the summer months, the thermal inertia of a home with a cavity brick construction takes longer to heat up in contrast to a lightweight residence.
At a thorough study instigated by the Australia brick sector using high-income home modules it was discovered that, increasing thermal mass, raises thermal lag. In fact during the summer, the outside temperature might reach its highest around 13:00, but the interior temperature may not until about 18:00 or 19:00.
Additionally, the maximum temperature experienced within a lightweight home was considerably greater compared to that experienced in a cavity brick house. The temperature fluctuation inside the lightweight house also closely followed the external temperature profile. In comparison, the heavier cavity brick home attained its maximum internal temperature a few hours after the daily external maximum was undergone. The thermal lag supposed that heating was also being attracted from the brickwork and back into the atmosphere as the external temperature dropped throughout the daily cycle, reducing the amount of heat available to be transferred into the house, leading to greater levels of thermal comfort when compared with the lightweight house, and decreased requirements for energy hungry air conditioners.
Insulation and Sealing
Heat naturally flows from warm areas to colder regions. It can do this via three mechanisms:
The majority of national (thermal) insulation products operate to stop conduction and will be found in the ceiling and walls. This means throughout the cooler months, a properly insulated home will function to reduce heat from escaping from dwelling spaces. Conversely, in the warmer months, the insulating material works to minimise heat going into the living spaces from the exterior.
Convection is the organic flow of thicker, thicker fluids or gases to lower degrees. A properly sealed home will prevent warm air from entering during the summer months through leaky doors, doors and even floors. In the same way, a sealed residence will stop the loss of heat during the coolerwinter months.
Here, good local knowledge of the place is invaluable. While windows should be located to take advantage of passive solar heating, the window orientation and type should also consider the ability to permit breezes to ventilate the home to help flush out heat in the summertime. Fantastic ventilation may also benefit air quality within the dwelling.
While a correctly designed home can provide energy savings, active users, i.e. people who know the solar passive design fundamentals and can implement them, will deliver the greatest benefits. Such activities would include opening windows specific times to use breezes to flush unwanted heat in the house and using shade devices such as awnings to restrict heat going into the home in warmer months.
Solar passive design principles are an efficient approach to decrease the energy consumption and greenhouse gas emissions of a house. They need to be contained in the first house design to have maximum impact, but can be applied to existing houses and provide significant advantages. When coupled with active users, families will generate the maximum environmental and economic advantages.