Wednesday, April 15th, 2015 Blog by Kendall Cooper Shading your air conditioner’s outdoor condenser unit is an accepted way to increase its efficiency and lower your cooling costs. That’s because shading the air conditioner is said to cool down the air around it, so that it doesn’t have to work as hard to cool that air before blowing it into your house. But can shading your air conditioner really make it more efficient? If so, what’s the best way to go about shading your air conditioner? It may be worthwhile to shade your air conditioner if you can create a large shaded area, such as that created by an awning or, better yet, one or more trees. Shrubs and bushes can also cool the air around your air conditioner; just make sure you don’t block the unit’s air flow. If possible, place your air conditioner unit on the north side of your house. According to the U.S. Department of Energy, shading your air conditioner with trees can make it as much as 10 percent more efficient.

But the benefits extend beyond improving your air conditioner’s efficiency. Shading your home with as few as three trees can save you between $100 and $250 a year in cooling costs, and can slash your air conditioning costs by as much as 50 percent. That’s because shade trees cool the air around them, by preventing sunlight from heating the ground. They also block sunlight from entering your home through its windows, to help keep your home cooler. Air conditioners that operate in a cooler environment, such as one shaded by trees, bushes, or an awning, operate more efficiently, because they don’t need to work as hard to cool down air that is already somewhat cool. Shade can also be used to cool down paved areas around your house, and prevent them from absorbing and releasing heat. If you live in a brick or stucco home, your very walls could be absorbing heat that could warm up the air around your air conditioning unit. A large awning on that side of the house could help keep the air around your air conditioner cooler.

Awnings over other windows could help the cool air inside your home stay cool. If possible, install your air conditioner on the north side of your house. You can still shade your air conditioner if it’s on another side of the house, but the north side stays the coolest throughout the day. Whether your air conditioner is on the north side of your house or on another side, you’ll need to do more than simply build a small awning over it in order to effectively cool enough of the surrounding air to impact the air conditioner’s efficiency. What you’ll need to do is plant trees, shrubs, and bushes. If your air conditioner is on the south side of your house, go for trees that grow tall and have expansive crowns with plenty of foliage. If your unit is on the east, west, or north side of your house, you can stick with trees that grow lower to the ground if you want. A six to eight-foot-tall deciduous tree will begin providing some shade for your air conditioner within a year of planting it.

If you want to shade all of your home’s windows — and not just the air conditioner itself — give priority to trees planted west of the west-facing windows. You can plant these trees no further than 20 feet from the windows. do portable ac units really workChoose trees that will grow about 10 feet taller than the windows.prices for hvac systems To truly maximize your air conditioner’s efficiency, you’ll want to plant at least two or three trees on that side of the house. how to make my ac unit quieterYou should also plant shrubs and bushes near the air conditioner, but not so close that they hamper air flow into the unit. Bushes and shrubs help cool the air above them because they stop the ground from absorbing the sun’s heat.

The more trees and bushes you can plant near your air conditioner, the cooler the air around it will be and the more efficiently the unit will function. You want to focus on creating a large area of cooler air, so that the unit doesn’t simply pull hot air from beyond the shaded area. If there are paved areas or walkways near your air conditioner, make sure they’re also well-shaded. Low-growing shrubs may be sufficient for some areas, such as walkways. Pavement absorbs more heat from the sun than soil, causing the air above it to be that much warmer. If you have a large patio on that side of the house, it may be worthwhile to install an awning over it. Shading your air conditioning unit can help the unit work more efficiently, cut your cooling costs and lengthen your air conditioner’s life. Trees and shrubs also help keep the air inside your house cool, and can increase your enjoyment of your outdoor space.Today I wanted to share some info about air conditioning on a solar panel system. 

Charlotte’s heat really came full force this week.  I know for many their climate doesn’t get as humid as it does here, for us here, AC is pretty key.  Without AC I can’t really sleep, even with a fan and my house being passive cooled.  While the humidity is still pretty comfortable, it’s HOT and the humidity is coming.  It has been in the high 80’s and low 90’s outside, which made my house in the mid 90’s inside. I thought I’d do a post today because I’ve been able to run some real world experiments with my tiny house, the AC and solar.  I haven’t seen any real world into practice reports on this stuff, so I figured it would be helpful for you all. I have yet to hook up my mini split system because it has taken me a long time to find a HVAC installer that would install my mini split, the reason being they all want to sell you the equipment if they are going to install it.  This was an unknown factor to me when I ordered my unit, but these are the bumps in the road you experience when you live The Tiny Life.

For heating and cooling I opted for the Fujitsu 9RLS2 which is a 9,000 btu unit with a seer rating of 27.  To give you an idea, older systems have a SEER of around 8 to 10, modern systems that are labeled highly efficient have a rating of 15 or so, but most today are around 12-13.  This is very important because me being on solar, my system simply couldn’t handle the less efficient systems.  Read about my tiny house solar panel system by clicking here.  The SEER rating is simply a function of BTUs (British Thermal Units) to Watts.  The higher the number, the better. The other big reason I choose this unit versus a window unit was that my air handler is wall mounted, out of the way and above eye level.  This does a few things:  keeps my limited square footage clear of stuff, it keeps my windows looking nice because I don’t have a window unit blighting a good design, and keeping it above eye level also makes you forget about it because as humans we don’t often look up.

While I’m trying to get an installer lined up I’m using a Portable Air Conditioner which has worked pretty well.  The downside to it is it takes up a lot of space and it’s not as efficient; it has a SEER rating of 12, which makes my mini split system 225% more efficient than this. I decided to “stress test” my system by turning the Portable AC unit on high and setting the thermostat to 60 degrees and see how long it was going to take for my batteries of my solar panel system to bottom out (50% discharge).  The charge controller on my system automatically turns off the power to my house if the power in that batteries discharges down to 50%, this allows me to not damage the batteries by discharging too deep. As you can see by the chart above, keeping discharge at 50% or above gives me a little shy of 2,000 cycles or 5.4 years.  I plan to add another set of four batteries to the system pretty soon, which will give me a good capacity and keep my discharge rate much higher than 50% (though I don’t often get that low)  In about 5 years we should start seeing some really interesting battery technologies hit market, so I plan to hop on that as soon as my batteries begin to fade.

My stress test turned out pretty good.  With the much less efficient portable air conditioner I ran it solid for 3 days starting with a very warm house.  At the end of the three days I was very close to hitting 50%, but it didn’t ever dip below.  I decided that the test went on long enough to be pretty happy, so I decided to stop.  I typically turn off the AC when I’m gone. The past few days have been a bit trickier because since my system was so low from the stress test, I needed it to build back up, but we have had a series of cloudy days.   I’ve had plenty of power to run the AC over night, but it’s lower than I’d like.  To give you an idea, on a normal sunny day I make about 8,000 watts, on a cloudy day I get between 2,000 and 4,000 watts when the clouds are very thick with no gaps. The really great thing is when it’s hottest, during the day, I can make lots of power.  This allows me to run the AC full blast and I can make enough power to run the AC and still be dumping 1000 watts into the batteries. 

Compare this to heating, you most often need the heat at night the most, which is when the sun isn’t out, so its a major drain on your batteries.  To compound the issue of heating, heaters are often more energy intensive than cooling. The other night I tried an experiment.  I got my house very cold and turned off the AC at midnight (when I usually go to bed).  Outside it was pretty cool, about 65 degrees and about 45% humidity, so not bad.  I left all the windows closed to see how much my body heat would heat up the house and because in the summer, opening the windows doesn’t help even if it is cooler outside because the humidity increase the “feels like” temperature. As it turns out in just three hours my body heat warmed the loft of my tiny house up to the point that I woke up from being so uncomfortable from the heat.   Around 3:30 am I woke up and it was very hot in my loft.  I checked the time and was surprised how little time it took.  I should note that I’m one that when I fall asleep, I stay asleep all night, even if I get warm, so the fact that I was woken up goes to show how uncomfortable I must have been, because it takes a lot.