How To Save On Heating and Cooling
Thermal management of buildings has always been hindered by obstacles, and it is often costly. In this article, I will attempt to assist you with the process of maintaining a comfortable temperature in your home during the summer and winter seasons. The solutions to heating and cooling problems vary widely by area. Sometimes high humidity is the most significant part of the problem, sometimes it is a high temperature, a lack of ventilation, a lack of proper insulation, or a combination of all of the problems above. I thought about all of these recommendations carefully and tried them, and they help, as a matter of fact, they work perfectly depending on your geographical location and nature.
Table of Contents
- Choosing the Right Air Conditioner
- Heating Methods
- Radiant Floor Heating
- Reverse Cycle Air Conditioning
- Water Heating
- Stoves and Cooking
- Refrigeration and Freezing
- Making a Smaller Refrigerator Work
Conventional vapour compression air conditioning effectively cool the areas that they are operated in when used as instructed, but, they have a high cost of ownership, their power consumption is high (between 500 watts and thousands of watts for residential units), and their price tags are also high. Therefore, some people need alternative temperature control methods. Read more about how air conditioners work
- In the U.K, it would cost £61.15 per 28 day month to leave a 2600 watt air conditioner running for 12 hours per day, if the cost of electricity was £0.07 per kWh, and you would have used 873.6 kWh of energy.
- In Germany, it would cost €165.98 if the rate was €0.19 per kWh.
- In Norway, it would cost 436.80 Krone if the rate was 0.50 Krone per kWh (same as Sweden).
- In the U.S, it would cost $96.09 USD if the rate was $0.11 USD per kWh
There are numerous ways in which people can keep their area comfortable, or at least make themselves more comfortable, such as:
- Open the windows for ventilation and do not leave anything in front of them. Important Note: For increased safety, install quick-release burglar bars (openable burglar bars) or you can use permanent burglar bars on one of the windows in the room and open that one, while the others remain openable in the event of fires, but secure (sometimes) because they are closed.
- Point a standing/pedestal fan at yourself (the key to make this work is to actually point the fan directly at you, do not use the fan to circulate the hot air in the room, that is not nearly as effective). Here is an example of one. Take your time and position it in such a way that it cools you best. A typical standing fan may be rated at 40-60 watts. Please keep the fan clean, as dirt, and dust bunnies accumulate in the spaces in the grille, they slow down air flow, and that will make you uncomfortable. Note: Fans are much less effective without adequate ventilation because humidity accumulates and fans cool your skin by accelerating the evaporation of your sweat.
- If you are using conventional A/C, close all of your windows and doors. You can also purchase a unit with an inverter, which adjusts the speed of the compressor motor based on the temperature of the room. Do not even leave the smallest opening open. They recirculate the air in the room which was already cooled, and they maintain that temperature. Letting hot air into the room will inhibit that process and the inverter won’t be able to save you much electricity nor money.
- When using conventional A/C, if you tend to leave it on because you don’t want to wait for it to cool when you get home, then program the thermostat to turn it on 30 minutes before you arrive and then shut itself off just in case you come home late. If you come home late and it is still on then it is going to waste electricity. Only program it to do this if your house is decently insulated. If it is not, then it will get hot again very quickly and it won’t be very helpful. It would just be a waste of electricity.
- If you are using air conditioning, turn the thermostat temperature up as much as you can bea and point a standing fan at yourself, I recently found this to be very effective.
- Do not use a single large window or split air conditioning unit to cool more than one room. This results in uneven, inefficient cooling, plus the room that the unit is installed in will be too cold as well. Also, the thermostat adjusts the air conditioner based on only one room. If you want to cool multiple rooms, you are to set up one unit for each room or central air conditioning.
Choosing the Right Air Conditioner
When shopping for air conditioners, please select the correct size for your room. If you purchase a unit that is too large, then ideally it would just cool faster and shut off sooner, but there is a consequence.
It is inefficient, and will leave the room too humid. If your room is 100-150 square feet, then purchase a 5,000 BTU unit, if your room is the rest of these sizes, purchase the unit to the right of your room size, ignore the BTU per square foot figures if your knowledge is not advanced and the emboldened figures in square feet are what I used to calculate the BTU/square foot figures:
- 150-250 square feet: 6,000 BTU – 40 BTU/square foot.
- 250-300 square feet: 7,000 BTU – 28 BTU/square foot.
- 300-350 square feet: 8,000 BTU – 26.6 BTU/square foot.
- 350-400 square feet: 9,000 BTU – 25.7 BTU/square foot.
- 400-450 square feet: 10,000 BTU – 25 BTU/square foot.
- 450 to 550 square feet: 12,000 BTU – 26.6 BTU/square foot.
- 550 to 700 square feet: 14,000 BTU – 25.4 BTU/square foot.
- 700-1000 square feet: 18,000 BTU – 25.7 BTU/square foot.
- 1,000-1,200 square feet: 21,000 BTU – 21 BTU/square foot.
- 1,200-1,400 square feet: 23,000 BTU – 19 BTU/square foot.
- 1,400-1,500 square feet: 24,000 BTU – 17 BTU/square foot
- 1,500- 2,000 square feet: 30,000 BTU – 20 BTU/square foot.
- 2,000 to 2,500 square feet: 34,000 BTU – 17 BTU/square foot. [Source of entire table and more info]
- Use a window fan for ventilation if you are not using A/C, you can’t use both simultaneously (or preferably a water resistant fan, you can even use a standing fan, but don’t allow it to get wet). These may be rated at approximately 55 watts, and sometimes more. Please keep the fan clean, as dirt, and dust bunnies accumulate in the spaces in the grille, they slow down air flow, and that will make you uncomfortable.
- If you can point your ventilation fan at you, then do so. Ventilation fans are most beneficial when the air outside of your home is cooler than the air inside (and it often is), or if the humidity of the air inside your home is higher than the air outside, and they maintain a flow of fresh air into the home. I would recommend setting up a dust screen first.
- Wear thin and lightweight clothes which don’t insulate your body much. Do not wear multiple layers of clothing. If you want to follow current fashion trends, try to find shirts which make you look like you are wearing a different coloured shirt under another.
- If you have large windows, purchase blinds that you can close when it is sunny.
- Place something on your windows to block out sunlight. You can cover the windows with blinds, reflective tints, or replace them with frosted window glass (blinds and are more effective, though, and I wouldn’t bother with frosted windows), be sure to leave some windows clear enough for you to see through them.
- In the case of tints, tint all the windows, and only if you are in an area with no winter such as a tropical country, or in a location with hot summers and mild winters. You will need sunlight sunlight as a natural source of heat to help lower heating costs during the winter. Heating costs are low during mild winters, and cooling costs are very high. Florida is an example of such a place.
- Use an evaporative cooler if the humidity in your area is low. When using evaporative coolers, you must set them up in such a way that they draw air in from outside, and open a window on the other side of the room so that they can push warm, high humidity air out of the room.
- Try using a dehumidifer if your primary problem is high humidity (especially if it is in excess of 90%), and the temperature is not high. Some areas are not hot, but have extremely high humidity, and are still very uncomfortable. High humidity results in the slow evaporation of sweat, which causes you to feel uncomfortable and hot. The evaporation of sweat cools your body.
- If you are using central air conditioning, close the vents in the rooms which you seldom enter.
- Another method is to set your air conditioner’s performance to a very low setting and point the vents directly at yourself.
- Ensure that the filters and coils are kept clean, maintain them (and replace the disposable filters) prudently. Clogging can have a profound effect on performance and efficiency.
- Switch off your air conditioner whenever you leave your home.
EER (Energy Efficiency Ratio) and Average Air Conditioner Power Consumption
This is the ratio of cooling capacity to power consumption. To determine power consumption, divide the BTU rating by the EER.
Example: 5000 BTU / 9.7 EER = 515.46 Watts. 5000 BTU / 515.46 Watts = EER of 9.7.
Efficiency is usually in the range of 8 to 12 BTU/watt.
Average Maximum Power Consumption:
At an average cooling efficiency of 10 BTU/Watt, a:
- 5,000 BTU unit consumes: 500 Watts
- 9,000 BTU: 900 Watts
- 12,000 BTU: 1,200 Watts.
- 18,500 BTU: 1,850 Watts.
- 25,000 BTU: 2,500 Watts.
As with cooling, heating homes during the winter can be a costly and energy intensive task, unless you utilize some of the methods listed below.
- In the U.K, it would cost £52.08 per month to leave a 1000 watt heater running for 24 hours per day, if the cost of electricity was £0.07 per kWh, and you would have used 744 kWh of energy.
- In Germany, it would cost €141.36 if the rate was €0.19 per kWh.
- In Norway, it would cost 372 Krone if the rate was 0.50 Krone per kWh (same as Sweden).
- In the U.S, it would cost $81.83 USD if the rate was $0.11 USD per kWh
There are numerous ways in which people can keep their area comfortable, or at least make themselves more comfortable, such as:
- If you wear adequately warm clothing, you may not need to use a heater, depending on the temperature. Wear thick clothing. You can also turn the thermostat temperature down and wear warmer clothing while using the heater. That is a good alternative if you don’t want to wear very thick clothing. The colder the surrounding air is, the more heat is absorbs from your body, whatever you are wearing, this is why using the heater at a lower setting can help you to keep warm without running up your bill. Also try wearing thick socks and a hoodie.
- Switch off your heater when you are not at home, if your indoor pipes will not freeze. They need to be insulated. If your home is well insulated, try programming the thermostat to turn the heater on shortly before you get home and then shut itself off after the room warms, just in case you get home late, you would not want it to stay on for hours while no one at home is actually using it.
- Set the heater to a low setting and point the vents directly at yourself.
- Invest in insulation or choose a well insulated home if you are going to purchase another, insulation helps to trap heat inside your home during the winter, and can lower heating costs by slowing the dissipation of heat from your home.
- Invest in double or triple paned windows. Double paned windows allow the sun’s rays into the house, but they help to trap the heat from them inside the house as well.
- If you are using a central heating system, then close the vents in the rooms that you seldom enter, or do not plan to enter for an extended period of time.
- Adjust the heater in such a way that it keeps the home at a comfortable temperature, but without toasting it, you only need the temperature to be acceptable.
- Close the windows tightly, and ensure that there are no air leaks. Purchase weather stripping or insulating sealant (such as foam insulating sealant) for both your doors and windows. Open your window blinds/shutters to let in as much sunlight as possible. What you would do is spray a small amount of the foam sealant onto the bottom of the sill of sliding windows and then slide them down onto it. Please read the instructions on the can carefully first. You can also use it to fill large holes where cold air might blow in and heat may escape until you fix those holes.
- Please exercise caution and take preventative measures to keep mold under control. A dehumidifier with a humidistat will keep mold at bay, and power consumption will not be much of an issue because the dehumidifier will not have to operate for a long time if the rooms are thoroughly sealed.
- Remove or cover anything containing water so that the water does not evaporate, and increase humidity.
- Do not leave your door open for long, if you are going outside, even for a short period of time, close it. The air inside can cool down quickly.
- When you are sleeping, use some form of electric blanket or bed warmer, or maybe even just an extremely thick and well insulated blanket, instead of leaving your heater on all night. It would cost $27.28 USD per month to leave a 1000 watt heater running for 8 hours per night, if the cost of electricity was $0.11 USD per kWh, and you would have used 248 kWh of energy, and £17.36 in the U.K if the cost of electricity was £0.07 per kWh.
Radiant Floor Heating
This is when heating elements or coils with a fluid in them (such as water) are used to radiate heat upwards from the floor, evenly heating a room without fans.
Reverse Cycle Air Conditioning
Traditional air conditioners are devices called heat pumps. They transfer heat from the evaporator coil (which is inside the air handler unit in the building) to the condenser coil (which is outside of the building). The compressor also generates its own heat, and that heat is also transferred to the condenser. This cycle (called the vapour compression cycle) can be reversed so that heat is pumped from the cold air outside into the evaporator coil inside, and the evaporator coil is then used in a way similar to a radiator and air is circulated between its fins. When an air conditioner operates in reverse, the evaporator inside does the job of the condenser, and the condenser outside does the job of the evaporator. So in normal mode the evaporator absorbs heat and transfers it to the condenser using refrigerant, and in reverse cycle mode, the exact opposite happens. Reverse cycle air conditioning is very efficient. It can transfer 3 units of heat per unit of electricity consumed.
To learn more about the details of this vapour compression process, visit this page: Vapour Compression Cycle
- Create a chore schedule and move clothes drying to night time if your power company offers cheaper electricity rates at night.
- If you must have one or two pieces of clothing dried immediately, you can place them in front of a fan in such a way that air won’t escape, the fan will pass warm air through the clothing and that will accelerate evaporation. If you totally cover the front of the fan with a shirt (for example), the shirt can dry in a little over 15 minutes, clothes pin all ends of the shirt to the sides of the fan, you can also place the shirt in front of the fan, turn it up to the highest setting (I used a 60 watt fan) and it should dry in 30 minutes, and consume less than 30 Wh of energy, use this method if you don’t have a clothes iron, otherwise, use the iron to smooth and dry them.
- If you must have one or two pieces of clothing dried quickly, and during the winter, place them in front of your heater, or in a heated room. If your house is kept at a fairly warm temperature, you won’t need to put them in front of a heater.
- Purchase a retractable clothes line and hang your clothes on that, drying time varies with temperature and humidity, but your clothes will always dry. These can be obtained for a mere $10 USD. Your clothes should dry in an afternoon.
- Purchase a foldable clothes rack (which may cost a mere $25 USD, or even £13) if space is limited, so that you can easily fold it and put it out of sight.
- Clothes dryers shrink clothing sometimes, and you may also have to iron your clothes after drying them in the dryer. I don’t have to iron mine after they dry on the clothes line.
- Clothes dryers can be a potential fire hazard if you are not careful, read more about that here: Consumer Product Safety Comission
Some water heaters consume up to 6000 watts, and the way in which they are used is sometimes energy inefficient. I will list more energy efficient ways to heat water, as well as more efficient ways to use conventional water heaters. If electricity cost $0.11 USD per kWh, and you had a 6000 watt heater, then it would cost you $491 USD per month to leave the heater on all day. Some people do this, and it is not necessary. If that same water heater was left on for 2 hours per day, at a rate of $0.11 USD per kWh, then it would cost $41 to operate per month, and for 10 minutes per day, it would cost $3.41 USD per month.
- Create a chore schedule and move your daily bath to night time if your power company offers cheaper electricity rates at night.
- Modern electric water heaters (and even some older ones) can heat water adequately within five minutes of turning them on, so turn on yours for only five minutes, and then use that to shower. It is not advisable to leave it on. It will keep turning itself on to reheat the water at times when you don’t need it.
- Modern electric water heaters are insulated, and can keep water hot for many hours throughout the day. Whenever you want hot water, turn on the hot water pipe to see if it is hot, and then use it, if not, then turn on the heater.
- If you want the convenience of having hot water all day, and without consuming electricity at all, then think about a solar powered water heater.
- If you and/or those living with you tend to leave your tank water heaters on for extended periods of time, a tankless water heater might help because people have to leave tank heaters on because they take a while to heat water, but the tankless type is only turned on when you need hot water. Tankless water heaters are also very convenient because of this. One disadvantage is a high price tag. The economical advantages or disadvantages of switching to a tankless water heater vary with geographical location.
Stoves and Cooking
People frequently have the following question to answer when purchasing their next stove: “Should I buy an electric stove or a gas powered one?”
The answer to that question varies with geographic location. The main determining factor of which is more economical is the cost of gas (usually LPG, which is Liquified Petroleum Gas) compared to the cost of electricity per BTU (British Thermal Unit). Some people are also concerned about the environmental impact of their stoves. This is dependent on what the power plant powering it is fueled by or what fuel you are using to directly power the stove. The fuel is often LPG which is either propane, butane, or a mixture of the two. The power plant may be fueled by coal, natural gas (which is much cleaner than coal), nuclear, solar, or wind. A coal power plant emits far more pollutants than an LPG stove does. You can call your power company and ask them what the main fuel is.
Refrigeration and Freezing
Making A Smaller Refrigerator Work
Smaller refrigerators use less energy overall than larger ones. Don’t confuse this with efficiency which is sometimes better in larger refrigerators. What matters in this case is how much power they actually consume overall.
- Make a little time to experiment with positioning items in the refrigerator and freezer in such a way that they occupy as little space as possible.
- Avoid placing items that do not need to be refrigerated into the refrigerator (bread freezing until you are ready to use the bag is understandable, though, it is very helpful). If the label says to refrigerate after opening then do so. Many fruits such as oranges, bananas, mangoes, plantain, and more can last a long time outside of the refrigerator.
Other items that can last long outside of a refrigerator or which don’t need to be refrigerated include: Thyme, potatoes, onions, pepper and hot sauces (please read the label carefully, some times require refrigeration), unopened boxes of milk (not if they are in the supermarket refrigerator), and whatever else is not in the supermarket refrigerators, but I need to remind you to check the packaging for refrigeration notices.
- There are common claims that your refrigerator is a certain percentage of your overall electricity usage. This is an average and it does not apply to many people because total electricity usage varies considerably. If your fridge consumed 92 kWh per month and your total electricity usage was 515 kWh per month, then the refrigerator accounted for 17% of your electricity consumption (92 / 515 * 100). If another person with the same refrigerator consumed a total of 615 kWh per month, then the refrigerator’s percentage drops from 17% to 15% (92 / 615 * 100).
- Ensure that your refrigerator’s seals are fully functional. Refrigerators turn themselves off when they become cool to save energy, but when the air inside them warms, they switch on, so if your seals allow warm air to enter your refrigerator, it will stay on too long and waste a great deal of electricity.
- When purchasing a refrigerator, please choose from the different types carefully based on your needs. Top and bottom freezer types have small freezers for storing few items, which is adequate for many people, but not all, and there is the type which is divided down the middle (one door on either side) which has a very large freezer for those who store many items in their freezer. Choose which you need more, refrigerator space, or freezer space.
- Always remove what you want from the refrigerator and immediately close the door(s), read the suggestion above for more information.
- Try to upgrade your refrigerator to a modern one, modern energy efficient refrigerators can save you an ample sum of money.
- Try to avoid using more than one refrigerator.
- Turn off the anti-sweat feature which prevents condensation at the sides of the refrigerator. It is a trade off. You can either save energy and let condensation take place, or you can keep it dry.
- Please ensure that nothing is obstructing airflow to or from the condenser at the back of your refrigerator. It is where heat is dissipated. Obstructions may reduce performance and efficiency. The condenser fins also need to be kept clean. Also ensure that nothing is obstructing the cold air vents inside the refrigerator and freezer compartments.
- If you hear any hissing noises, then it is a possibility that the refrigerant is leaking from the coils. Please take care of any leaks immediately, because the contents of the refrigerator will rot, and it will continue to consume electricity because it won’t become cold enough to turn itself off. Refrigerators turn themselves off when they become cool to save energy, but when the air inside them warms, they switch on.