After talking about the best way to save energy in your home or business, its time to talk about the most practical, and probably cheapest, way to lower your bills.
>Jason: Although it isn't the highest user in your home, lighting comprises on average 15% of the total energy usage in your home. Newer homes are usually more efficient, because they are often built with fluorescent lighting in kitchens and garages, compact fluorescent lamps in porch lights and can lights, and the newest homes are often being built with automatic light switches. Older homes, however, are almost always lit with standard incandescent lights. (the light that Thomas Edison invented) Strangely enough, we don't stop to realize that we use a 100+ year old invention every day that hasn't been improved at all. Of course there is a more efficient way to light your home.
If you are like most people, your impression of fluorescent lights is that they are greenish, and give people headaches. This has changed tremendously in the last ten years. Fluorescent lights now compete with incandescent lights in all aspects, except that they are four times more efficient. Lighting is measured in two basic figures, color temperature and color rendition. Temperature is measured in Kelvin, which means the color of an object if it was burning at that degree Kelvin. Rendition is the accuracy of the colors. Incandescent lights reproduce almost every color perfectly, giving it a color rendition index (CRI) of 100. compact fluorescent lights, or CFLs, are anywhere from 75 - 92 CRI. 75 is a little bit unrealistic, and will make objects appear cold, but 90+CRI is very good. Ken, tell me a little bit about CFLs.
>Ken: CFL's, or compact fluorescent lights, are a great way to improve your lighting, lower your bills and actually lower the heat generation in your house all at the same time. If you like to use 100 watt light bulbs in your home, you can get the same amount of light and even the same yellow appearance of that 100 watt light bulb with a 23 watt CFL. What is nice is that you have options with the color of the bulbs with CFLs. If you want a whiter light for reading, or detail work, there is a CFL for that, or you can get a warmer light for "atmosphere". The color of the light is measured in degrees of Kelvin. A 2700K light will be similar to your average incandescent light bulb, a 5100K light will look more like a very white or almost blue light.
>Jason: CFLs are very popular right now because they are so efficient, and the prices have dropped a lot. Check your local utility company for incentives on replacing your incandescent lights with CFLs, they may even put them in for free! If you do this change, you can reasonably expect your electric bill to decrease by 11%. Thats figuring 75% reduction of your lighting costs, which are 15%of your total bill. Thats a good number. In the future we may talk about even more efficient options, like LED, but for now, get your lights replaced and be Energy Smart!
Sunday, June 28, 2009
Sunday, June 21, 2009
Does Your House "Suck"? Ducting for your AC
>Ken: Ducting, what a truly boring subject. This could be wasting you lots of money and energy by cooling or heating your attic or crawlspace (wherever your ducting is located). Ducts are not the birds we like to eat at holiday time, rather they are those metal or plastic tubes that move the air to and from your air conditioner and the rooms in your home. I spent the better part of 2 years testing ducts for tightness in the Fresno, Ca. area, and found that the average home's ducts leaked about 30%-50% of your conditioned air into the attic or crawlspace. While this obviously costs you money, it can also be dangerous to your health.
Return air leakage is the worst culprit for costing you money. It is sucking in attic air (assuming the ducts are up there) at possibly 130 or 140 degrees Fahrenheit. When the AC conditions your air, it takes partially conditioned air from your home and cools it by about 20 degrees. You can see that if it is pulling in 140 degree air from your attic and mixing it with what you have inside your home that what it delivers back into your home won't be anywhere near as cool as you want.
>Jason: An air conditioner is designed to deliver exactly the same amount of air as it pulls out. When you send air into your attic, you are preventing the air from returning to your home. Since the air came out of your living space, you create a vacuum, sucking air in from wither the outside or from your attic. This air will not be nicely filtered and usually has lots of contaminants. The air in your house can be up to 100 times worse than the outside. So if your ducts leak, you are conditioning your attic and you are poisoning your air! So how do you know if your ducts leak? Its a simple procedure that most HVAC contractors can do called a duct test.
>Ken: Your ducting should not be leaking any more than about 15%, and should be much less (about 5%) if the home is less than 5 years old. Many HVAC contractors will do a duct test for a very low cost. Duct seals may receive a rebate from your local utility. Let us know who your utility is, and we can research for you what is available.
>Jason: To wrap this up, one easy way to determine if your ducts are leaking is to look for dark lines along the edges of carpet or around your supply vents. This is an indicator that you are sucking dirty air in from the outside. You can also turn your system on and unlatch an outside door. If the door pulls inward, you have negative pressure on the inside of your home, which means you have leaky ducts. So until next time, dont let your house "suck" and be energy smart!
Return air leakage is the worst culprit for costing you money. It is sucking in attic air (assuming the ducts are up there) at possibly 130 or 140 degrees Fahrenheit. When the AC conditions your air, it takes partially conditioned air from your home and cools it by about 20 degrees. You can see that if it is pulling in 140 degree air from your attic and mixing it with what you have inside your home that what it delivers back into your home won't be anywhere near as cool as you want.
>Jason: An air conditioner is designed to deliver exactly the same amount of air as it pulls out. When you send air into your attic, you are preventing the air from returning to your home. Since the air came out of your living space, you create a vacuum, sucking air in from wither the outside or from your attic. This air will not be nicely filtered and usually has lots of contaminants. The air in your house can be up to 100 times worse than the outside. So if your ducts leak, you are conditioning your attic and you are poisoning your air! So how do you know if your ducts leak? Its a simple procedure that most HVAC contractors can do called a duct test.
>Ken: Your ducting should not be leaking any more than about 15%, and should be much less (about 5%) if the home is less than 5 years old. Many HVAC contractors will do a duct test for a very low cost. Duct seals may receive a rebate from your local utility. Let us know who your utility is, and we can research for you what is available.
>Jason: To wrap this up, one easy way to determine if your ducts are leaking is to look for dark lines along the edges of carpet or around your supply vents. This is an indicator that you are sucking dirty air in from the outside. You can also turn your system on and unlatch an outside door. If the door pulls inward, you have negative pressure on the inside of your home, which means you have leaky ducts. So until next time, dont let your house "suck" and be energy smart!
Saturday, June 13, 2009
Split Systems and Package Units
In our last post, we discussed some of the basics regarding Air conditioners. Hopefully it didn't put you all to sleep, because this time, we are going to talk about the two most common types of air conditioning and heating systems, split systems and package units.
>Jason: Both of these have the exact same components, and perform the exact same tasks - heating and cooling your home. The only difference between the two is layout. I'm going to start with the package unit. Being the least efficient of the two, package units combine the heat exchanger (your furnace) and the condensing unit (your AC) into one box, usually found on your roof. These tend to be less efficient because there has been less research and development due to lack of demand. This is because most package units are only found in the southwest (Nevada, California, Arizona and New Mexico). So if you are not in one of these states, skip ahead to split systems. If you have a package unit already, it is probably best to buy a new package unit when replacing your heating and AC rather than to redesign your entire AC system.
>Ken: OK, let's not get into the relative benefits of either one except to say that split systems are the most common, usually with the furnace in the attic and the condenser outside your bedroom window keeping you awake at night. If you're wanting to replace the units, try to purchase the most efficient units that you can afford. The absolute best units will have multiple stages of heating and cooling and variable-speed control of the fan. This gives the system the ability to operate at its highest speed of cooling or heating when you get home (after a hard day of work) to bring the house to a comfortable temperature the fastest. Then when the home is comfortable, the unit drops down to a very low level to maintain the temperature, which is a MUCH cheaper way to keep your home comfortable than if the unit is turning on and off every 10 minutes all night.
>Jason: So to wrap up, if you want to replace your existing system, first check to see if you have a package unit or split system. Then, depending on what you already have, ask contractors for their most efficient units, and prices. If you are replacing a split system, ask the contractor about variable speed fans and two-stage heating and cooling. This will scare them into thinking that you really know what you are talking about. Good luck, and until next time - stay Energy Smart!
>Jason: Both of these have the exact same components, and perform the exact same tasks - heating and cooling your home. The only difference between the two is layout. I'm going to start with the package unit. Being the least efficient of the two, package units combine the heat exchanger (your furnace) and the condensing unit (your AC) into one box, usually found on your roof. These tend to be less efficient because there has been less research and development due to lack of demand. This is because most package units are only found in the southwest (Nevada, California, Arizona and New Mexico). So if you are not in one of these states, skip ahead to split systems. If you have a package unit already, it is probably best to buy a new package unit when replacing your heating and AC rather than to redesign your entire AC system.
>Ken: OK, let's not get into the relative benefits of either one except to say that split systems are the most common, usually with the furnace in the attic and the condenser outside your bedroom window keeping you awake at night. If you're wanting to replace the units, try to purchase the most efficient units that you can afford. The absolute best units will have multiple stages of heating and cooling and variable-speed control of the fan. This gives the system the ability to operate at its highest speed of cooling or heating when you get home (after a hard day of work) to bring the house to a comfortable temperature the fastest. Then when the home is comfortable, the unit drops down to a very low level to maintain the temperature, which is a MUCH cheaper way to keep your home comfortable than if the unit is turning on and off every 10 minutes all night.
>Jason: So to wrap up, if you want to replace your existing system, first check to see if you have a package unit or split system. Then, depending on what you already have, ask contractors for their most efficient units, and prices. If you are replacing a split system, ask the contractor about variable speed fans and two-stage heating and cooling. This will scare them into thinking that you really know what you are talking about. Good luck, and until next time - stay Energy Smart!
Tuesday, June 9, 2009
Air Conditioning Efficiency
>Ken: This week we will be talking about air conditioning, and how it affects your utility bill. First, the older your unit, the more it will cost you to run it. Think of it as you would your car, the higher the gas mileage the cheaper it is to operate. The same with your AC, the higher your SEER rating of the unit, the cheaper it is to operate. the SEER of your unit could be anywhere from 1-20, depending on the original SEER rating, age and condition of the unit. The condition of the ducting can also affect it, but we will discuss that in a later blog. So if your unit runs at 6 SEER, and you purchase a 12 SEER unit, you just cut the cost of operating your AC in half.
>Jason: Secondly, what is SEER? SEER stands for the Seasonal Energy Efficiency Rating. This rating is an average of the yearly usage of a unit, assuming that the AC is run all the time. Of course this figure is based on laboratory tests where the AC is cooling 82 degree air to 80 degrees. Since this isn't hard to accomplish, the SEER is generally higher than an Air Conditioner can actually perform. What's worse is that this lab test can vary depending on the company performing it. That is why there is another rating available, which is simply the EER, or the Energy Efficiency Rating. This is a standardized test in which an Air conditioner is cooling 95 degree air to 80 degrees constant. The EER is thus always a lower, but more accurate number. When purchasing a new air conditioner however, the EER is not posted except in the specifications of the unit. So when shopping for an AC, you can usually count on a 2-3 point loss between SEER and EER. How high of an EER should you purchase? Well, that can only be answered by your budget. Federal Government regulates that no unit can be manufactured below 13 SEER, which is more like 11 EER. However, if your pocketbook can afford it, you may want to look at getting a higher efficiency unit. Remember that this rating is like the gas mileage on your car.
>Ken: There are other factors to consider with how efficiently your AC will run, but we will discuss those later. An interesting calculator showing how the different efficiencies may affect your utility bill can be found at The following AC calculator The type of AC unit you have will also have a bearing on how efficient a new unit can be when purchasing, but again, we will discuss that at another time.
>Jason: In closing, if you decide that its time to purchase a new air conditioner, be sure to question your contractor about the EER of the unit, and make sure that the contractor sizes the unit properly using a heat load calculation.
>Jason: Secondly, what is SEER? SEER stands for the Seasonal Energy Efficiency Rating. This rating is an average of the yearly usage of a unit, assuming that the AC is run all the time. Of course this figure is based on laboratory tests where the AC is cooling 82 degree air to 80 degrees. Since this isn't hard to accomplish, the SEER is generally higher than an Air Conditioner can actually perform. What's worse is that this lab test can vary depending on the company performing it. That is why there is another rating available, which is simply the EER, or the Energy Efficiency Rating. This is a standardized test in which an Air conditioner is cooling 95 degree air to 80 degrees constant. The EER is thus always a lower, but more accurate number. When purchasing a new air conditioner however, the EER is not posted except in the specifications of the unit. So when shopping for an AC, you can usually count on a 2-3 point loss between SEER and EER. How high of an EER should you purchase? Well, that can only be answered by your budget. Federal Government regulates that no unit can be manufactured below 13 SEER, which is more like 11 EER. However, if your pocketbook can afford it, you may want to look at getting a higher efficiency unit. Remember that this rating is like the gas mileage on your car.
>Ken: There are other factors to consider with how efficiently your AC will run, but we will discuss those later. An interesting calculator showing how the different efficiencies may affect your utility bill can be found at The following AC calculator The type of AC unit you have will also have a bearing on how efficient a new unit can be when purchasing, but again, we will discuss that at another time.
>Jason: In closing, if you decide that its time to purchase a new air conditioner, be sure to question your contractor about the EER of the unit, and make sure that the contractor sizes the unit properly using a heat load calculation.
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