Joe Blake
13th March 2014, 21:22
Over the past 3 or so years I have been replacing aluminium framed single glazed windows and hollow cored wooden doors with double glazing, to reduce the heat and noise entering the house. The house is a mid-'70s brick and tile roof, and when I first moved in, it would turn into a hot box during summer. I installed fibreglass batts in the ceiling space initially, about 7-8 years ago, which helped. As each window or door was replaced the temperature regime became more comfortable. In December 2013 I acquired a digital remote weather station which stored the data (15 minute interval readings) for downloading and analysis.
On 6 March I arranged for the installation of the final window and door, on the western side of the house. (There are two other windows/doors remaining, but they are opening into spaces which are isolated from the main body of the house.) Below is a table from the Bureau of Meteorology giving the mean maxima for the locality of Kalamunda, which is about 5 km to my north, so represents a fairly close approximation of my suburb.
Jan 30.4
Feb 30.3
Mar 27.7
Apr 23.8
May 19
Jun 16.4
Jul 15.4
Aug 16.3
Sep 18.3
Oct 20.6
Nov 24.5
Dec 28
Annual 22.6
This graph shows the readings from my weather station of the maximum temperatures from mid-Dec '13 to mid-Mar '14.
http://i82.photobucket.com/albums/j245/saxeharp/general10/MaxTempDaily_zpseb7549f9.jpg
Below are two graphs, showing the internal house temperature (red) and the external temperature (green) as measured by the weather station, and the amount of power consumed by my house daily. The vertical line in the centre shows the date of installation of the last door and window on the western side of the house. (There is a full width semi enclosed patio on this end of the house, but it has a section of transparent roofing to enable my electric trikes to recharge their batteries with their on-board photovoltaic panels. This was installed about 4-5 years ago.)
http://i82.photobucket.com/albums/j245/saxeharp/general10/Glazingtemp_zps82bcc094.jpg
(The (low) power consumption on the date of installation would be considered anomalous, since there was a huge hole in the wall brickwork and thus no point running the cooler.)
The graphs show that not only is the internal temperature of the house cooler overall, but also because I am not using the air conditioner to the same extent as previously I am using less power. The majority of power I DO consume is more than covered by that generated on my rooftop. When the internal temperature starts to rise steeply on the graph it is usually because I have turned off the air-con as it is starting to import power from the grid (usually at about 17:30 hrs). However, I did notice that as the day wore on, on a hot day the air-con would not be able to cope with the rising temperature, so the internal temp started rising at about 15:00 hours or thereabouts, even though there was plenty of power available.
So from this I feel that just having solar panels installed is not necessarily going to give you the optimum result. There are other factors to take into account as well, such as insulation etc.
Joe
On 6 March I arranged for the installation of the final window and door, on the western side of the house. (There are two other windows/doors remaining, but they are opening into spaces which are isolated from the main body of the house.) Below is a table from the Bureau of Meteorology giving the mean maxima for the locality of Kalamunda, which is about 5 km to my north, so represents a fairly close approximation of my suburb.
Jan 30.4
Feb 30.3
Mar 27.7
Apr 23.8
May 19
Jun 16.4
Jul 15.4
Aug 16.3
Sep 18.3
Oct 20.6
Nov 24.5
Dec 28
Annual 22.6
This graph shows the readings from my weather station of the maximum temperatures from mid-Dec '13 to mid-Mar '14.
http://i82.photobucket.com/albums/j245/saxeharp/general10/MaxTempDaily_zpseb7549f9.jpg
Below are two graphs, showing the internal house temperature (red) and the external temperature (green) as measured by the weather station, and the amount of power consumed by my house daily. The vertical line in the centre shows the date of installation of the last door and window on the western side of the house. (There is a full width semi enclosed patio on this end of the house, but it has a section of transparent roofing to enable my electric trikes to recharge their batteries with their on-board photovoltaic panels. This was installed about 4-5 years ago.)
http://i82.photobucket.com/albums/j245/saxeharp/general10/Glazingtemp_zps82bcc094.jpg
(The (low) power consumption on the date of installation would be considered anomalous, since there was a huge hole in the wall brickwork and thus no point running the cooler.)
The graphs show that not only is the internal temperature of the house cooler overall, but also because I am not using the air conditioner to the same extent as previously I am using less power. The majority of power I DO consume is more than covered by that generated on my rooftop. When the internal temperature starts to rise steeply on the graph it is usually because I have turned off the air-con as it is starting to import power from the grid (usually at about 17:30 hrs). However, I did notice that as the day wore on, on a hot day the air-con would not be able to cope with the rising temperature, so the internal temp started rising at about 15:00 hours or thereabouts, even though there was plenty of power available.
So from this I feel that just having solar panels installed is not necessarily going to give you the optimum result. There are other factors to take into account as well, such as insulation etc.
Joe