What are the top 3 home appliances that cost you electricity? A detailed explanation of the causes and energy-saving measures
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Have you ever found yourself struggling to keep your monthly electricity bill down and wondered, "Which home appliances use the most electricity?" Some home appliances consume a surprisingly large amount of electricity, and electricity bills can fluctuate greatly depending on how you use them.
Based on survey data from the Japan Energy Agency , this article identifies the top three home appliances with the highest electricity bills, explains the causes of their high consumption, and provides specific energy-saving measures. It also introduces energy-saving methods for home entertainment using Aestiquo's energy-saving projector ( Aestiquo P1 ), and shares tips for achieving both reduced electricity bills and a more comfortable lifestyle.
1. Top 3 Electricity-Intensive Home Appliances: The Data
According to the Japan Energy Agency's "2018 Household Energy Consumption Survey," approximately 70% of the electricity consumed by an average household comes from three home appliances: air conditioners, electric water heaters, and refrigerators. Let's take a closer look at the monthly electricity consumption and characteristics of each.
Air conditioner (cooling/heating)
Monthly electricity consumption : Approximately 300-800kWh (varies greatly depending on the season)
Characteristics : Consumption increases sharply during the cooling season (July to September) and heating season (December to February), and can account for 30 to 40% of the annual electricity bill. The greater the difference between the set temperature and the outside temperature, the greater the power consumption.
electric water heater
Monthly power consumption : Approximately 200-400kWh (stable throughout the year)
Characteristics : Because it keeps boiling water 24 hours a day, it consumes a stable, high amount of electricity throughout the year. The more hot water is supplied and the higher the temperature at which it is kept warm, the more electricity is consumed.
refrigerator
Monthly power consumption : Approximately 50 to 150 kWh (stable throughout the year)
Characteristics : Because it operates 24 hours a day, it consumes electricity continuously throughout the year, although its individual consumption is less than that of an air conditioner. The more frequently the door is opened and closed, the higher the internal temperature becomes, and the more electricity is consumed for re-cooling.
Comparison of monthly electricity consumption for major household appliances
| home appliances | Monthly electricity consumption (kWh) | Estimated monthly electricity bill (yen)* | Important Notes |
|---|---|---|---|
| Air conditioner (cooling season) | 500~800 | 15,000~24,000 | Raising the set temperature by just 1°C can save approximately 10% of electricity |
| electric water heater | 200~400 | 6,000~12,000 | The timer function lowers the temperature outside of the specified time period. |
| refrigerator | 50~150 | 1,500~4,500 | Consumption increases when the door gasket deteriorates. |
| washing machine | 30~60 | 900~1,800 | Low temperature cleaning function saves energy |
| Lighting (LED) | 20~40 | 600~1,200 | Replacing fluorescent lights with LEDs saves approximately 70% of energy |
| Aestiquo P1 Projector | 5~15 | 150~450 | Save an additional 30% on power when using Eco mode |
* Calculated based on electricity unit price of 1kWh = 30 yen
Tip: An air conditioner's power consumption is greatly affected by the "set temperature" and "usage time." For example, simply lowering the set temperature from 26°C to 25°C when cooling will increase power consumption by about 10%. Conversely, raising the set temperature from 26°C to 27°C will save about 10% on power consumption, so it's important to set the temperature as close to the outside temperature as possible.
2. The real reason why high-power appliances "eat up electricity"
The reason why air conditioners and electric water heaters consume a lot of electricity is because a specific "energy conversion process" requires a lot of electricity. By understanding the "mechanism by which electricity is consumed" of each home appliance, you can come up with effective energy-saving measures.
① Air conditioners: Requires a large amount of energy to "transfer heat"
The basic principle of an air conditioner is to "transfer heat." When cooling, indoor heat is expelled to the outside, and when heating, outdoor heat is taken inside. In order to perform this "heat transfer," a compressor is required to circulate the refrigerant at high pressure, and this compressor consumes approximately 70% of the air conditioner's entire power.
Factors that cause high power consumption: The greater the temperature difference between indoors and outdoors, the greater the load on the compressor, resulting in a sharp increase in power consumption. For example, if you try to keep the room temperature at 20°C on a summer day when the temperature is 35°C, it may consume approximately twice as much power as keeping the room at 26°C.
② Electric water heater: A huge amount of energy is required to boil water
Water has a "high specific heat capacity," meaning that it requires a lot of energy to raise its temperature by 1°C. An electric water heater heats the water in the tank to a set temperature (usually 60-75°C) and operates the heater intermittently to maintain that temperature. This "heating" and "heat retention" process is the main source of electricity consumption.
Example of energy required to boil water : Approximately 0.045 kWh of electricity is required to heat 1 liter of water from 20°C to 60°C. If a family of four uses 50 liters of hot water per day, approximately 2.25 kWh of electricity will be consumed just for heating, amounting to approximately 67.5 kWh per month (this increases further when the electricity required to keep the water warm is added).
3. Refrigerator: Continuous operation to "maintain a constant low temperature"
A refrigerator's compressor operates intermittently to maintain a constant temperature inside the refrigerator (4°C for the refrigerator compartment and -18°C for the freezer). Every time the door is opened, outside air (hot) flows into the refrigerator, raising the temperature, which starts the compressor again to cool it down, repeating the cycle.
Tip: Opening your refrigerator door once can cause the compressor to run for an additional 10-15 minutes. Reducing the number of times you open the door is the most effective way to conserve energy in your refrigerator.
3. Practical energy-saving measures for high-power appliances: Aim to reduce electricity consumption by 5,000 yen per month
By simply making small changes to the way you use your energy-intensive appliances, you can reduce your monthly electricity bill by several thousand yen. Below, we will introduce practical energy-saving measures for air conditioners, electric water heaters, and refrigerators.
① Air conditioner energy saving measures: Save 30% on energy by adjusting temperature settings and usage time
- Optimize the set temperature . Set it to 26-28°C when cooling and 20-22°C when heating. This is the temperature range that the human body feels comfortable in, and by minimizing the difference with the outside temperature, you can reduce the load on the compressor. For example, setting it to 26°C when cooling can save approximately 20% on electricity compared to setting it to 24°C.
- Make use of the timer function . Set the "Timer Off" function when you go to bed so that it automatically shuts off 1-2 hours before you wake up. Also, be sure to turn off the power when you go out (as standby power also consumes about 5kWh per month).
- Clean the air filter regularly. If dust accumulates on the air filter, the airflow will decrease, cooling and heating efficiency will decrease, and power consumption will increase. Clean the air filter with a mild detergent once every two weeks, dry it, and then reinstall it.
- Strengthen insulation : In summer, hang sunshade curtains on windows to block out direct sunlight, and in winter, apply insulating film to prevent heat loss through windows. This can reduce the load on air conditioners by about 15%.
② Energy-saving measures for electric water heaters: Save 40% on electricity by setting it to a fixed time
- Limit heating time with the scheduled time function <br>Set the "scheduled time function" on your electric water heater to heat only during times when your family uses hot water (e.g., 6am-8am, 6pm-10pm). During times when hot water is not in use, lower the temperature to below 50°C (just lowering the temperature by 10°C from the normal setting of 60°C can reduce heat retention electricity by approximately 30%).
- Reduce hot water usage. If you use a bath instead of a shower, limit the amount of hot water used to the minimum necessary. Also, replacing your shower head with a water-saving type can reduce hot water usage by about 30%, which will result in less electricity used by your electric water heater.
- Strengthen tank insulation . For older electric water heaters, install an insulating cover around the tank. This will reduce heat loss from the tank by about 20% and reduce the amount of electricity needed to keep it warm.
3. Refrigerator energy saving measures: Save 15% of energy by opening and closing the door
- Reduce the number of times you open and close the door <br>Try to take out everything you need at once. For example, when preparing a meal, take out all the ingredients you need at once and avoid opening the door frequently. Also, keep the inside of the refrigerator tidy so that you can find things quickly.
- Optimize the temperature settings inside the refrigerator compartment . Set the refrigerator compartment to 4-5°C and the freezer compartment to -18--20°C. These are the appropriate temperature ranges for storing food, so there is no need to set them too cold. For example, setting the freezer compartment temperature to -18°C can save approximately 10% on electricity compared to setting it to -25°C.
- Regularly check the gasket for deterioration . If the gasket on the refrigerator door deteriorates, outside air will leak in and cooling efficiency will decrease. Check the gasket regularly, and replace it if it is deteriorated (contact the manufacturer's support).
Expected reduction in monthly electricity bills due to power-saving measures
| home appliances | Power saving measures | Monthly electricity reduction (kWh) | Estimated monthly electricity bill reduction (yen) |
|---|---|---|---|
| Air conditioner (cooling season) | Set temperature 26℃ + timer | 150~200 | 4,500~6,000 |
| electric water heater | Fixed time setting + heat retention temperature drop | 80~120 | 2,400~3,600 |
| refrigerator | Reduced door opening and closing times + temperature optimization | 10~20 | 300~600 |
| total | 240~340 | 7,200~10,200 | |
* Calculated based on an electricity rate of 1kWh = 30 yen. Savings may vary depending on the season and usage.
4. Aestiquo P1 Projector for Energy-Saving Home Entertainment: 70% Less Energy Than a TV
Televisions, popular home entertainment devices, are surprisingly energy-intensive. For example, a 55-inch 4K TV consumes approximately 0.15 kWh of power per hour, which translates to approximately 13.5 kWh per month if used for three hours a day. The Aestiquo P1 projector, on the other hand, uses significantly less power than a television thanks to its energy-saving design.
Aestiquo P1 vs 55-inch 4K TV power consumption comparison
| device | 1 hour power consumption (kWh) | Monthly electricity consumption (kWh) when used for 3 hours per day | Monthly electricity bill (yen)* | Energy saving effect (compared to TV) |
|---|---|---|---|---|
| 55-inch 4K TV (typical) | 0.15 | 13.5 | 405 | - |
| Aestiquo P1 (normal mode) | 0.08 | 7.2 | 216 | Approximately 47% power savings |
| Aestiquo P1 (Eco Mode) | 0.05 | 4.5 | 135 | Approximately 67% power savings |
* Calculated based on electricity unit price of 1kWh = 30 yen
Aestiquo P1's power saving function: Eco mode saves even more power
The Aestiquo P1 is equipped with the following power-saving features, allowing you to reduce power consumption while enjoying home entertainment.
- Eco Mode <br>Pressing the "Eco" button on the remote control automatically reduces brightness to 70% to reduce power consumption. When used in a dark room, this can save approximately 30% on power with almost no noticeable degradation in image quality. Instructions for setting up Eco Mode are explained in detail in the Aestiquo P1 product manual .
- Auto Power Off Function : If no signal is detected for a certain period of time (30 minutes/1 hour), the device will automatically enter sleep mode and turn off if there is no signal for an even longer period (2 hours). This prevents unnecessary power consumption caused by leaving the device on carelessly.
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Long-life LED light source design
The LED light source installed in the P1 has a lifespan of over 30,000 hours (approximately 3.5 years of continuous use), consumes less power than conventional mercury lamps, and requires less frequent replacement, contributing to long-term cost savings.
Tip: If you use the Aestiquo P1 in Eco Mode with Auto Power Off, your monthly power consumption will be less than 4.5kWh if you watch for 3 hours a day. This will save you about 270 yen a month compared to a 55-inch TV. This will save you about 3,240 yen a year.
5. Energy-saving measures for other home appliances: Don't overlook standby power
In addition to high-power appliances such as air conditioners and electric water heaters, other home appliances that we use on a daily basis also consume "standby power," which can have a surprising long-term impact on our electricity bills. Below, we will introduce energy-saving measures for other home appliances and ways to reduce standby power consumption.
Standby power consumption of major home appliances and power saving measures
| home appliances | Standby power for one month (kWh) | Monthly electricity bill (yen)* | Power saving measures |
|---|---|---|---|
| tv set | 2~5 | 60~150 | If you will not be using the product for a long period of time, unplug the power cord. |
| washing machine | 1~3 | 30~90 | Turn off the power when the washing is done |
| Game consoles | 3~8 | 90~240 | Turn off sleep mode and unplug after use |
| Outlet strip (multiple devices) | 5~10 | 150~300 | Use a power strip with a main switch and turn it off when you leave |
* Calculated based on electricity unit price of 1kWh = 30 yen
Three ways to reduce standby power consumption
- Use an outlet strip with a main switch. Connect multiple appliances, such as a TV, game console, and DVD player, to a single outlet strip and turn off the main switch when they are not in use. This will reduce the standby power consumption of multiple appliances at once.
- Choose appliances with "zero standby power" functionality . When purchasing new appliances, choose products with "zero standby power" or "energy saving grade A." These products have standby power of 0.5W or less, which can reduce your electricity bill in the long term.
- Regularly check your electricity usage. Use a smart meter or energy management app to check your household's energy usage in real time. This will make it easier to spot unnecessary energy consumption and raise awareness of energy conservation.
6. Summary: Key points for reducing electricity bills
There are three key points to reducing household electricity bills: "optimizing the use of high-power appliances," "reducing standby power consumption," and "utilizing energy-saving devices." In particular, with regard to three home appliances - air conditioners, electric water heaters, and refrigerators - even small changes in how they are used can result in significant energy savings.
Summary of key points for reducing electricity bills
1. Air conditioner : Set the temperature to 26-28°C for cooling and 20-22°C for heating, and use the timer function.
2. Electric water heater : Set a fixed time to suppress heating outside of the usage time and lower the temperature to keep the water warm
3. Refrigerator : Reduce the number of times the door is opened and closed to optimize the internal temperature
4. Standby power : Use a power strip with a mains switch to prevent unintentional power consumption.
5. Energy-saving devices : Use energy-saving projectors like the Aestiquo P1 to reduce power consumption for home entertainment
Reducing your electricity bill doesn't require making big changes all at once, but can be achieved by making small, everyday habits. For example, even simple measures such as raising the air conditioner temperature by 1 degree, setting a fixed time for your electric water heater, or using the eco mode on your Aestiquo P1 can reduce your monthly electricity bill by several thousand yen.
Please try out the energy-saving measures introduced in this article to reduce your electricity bill and enjoy a comfortable life. For more information on how to save energy for home entertainment using the Aestiquo P1 projector, please visit the Aestiquo official website .
7. Frequently Asked Questions (FAQ)
- Q: Does the "dehumidification mode" of an air conditioner save more energy than the cooling mode?
- A: Yes, dehumidification mode often saves more energy than cooling mode. In dehumidification mode, reducing indoor humidity is prioritized and the set temperature is automatically adjusted to 24-26°C, so there is no need to set the temperature as low as in cooling mode, reducing the load on the compressor. Using dehumidification mode is effective during periods of high humidity, such as the rainy season.
- Q: If I set the electric water heater to run at a fixed time, will there not be enough hot water?
- A: If you set the scheduled time to match the times when your family uses the hot water, you will almost never run out of hot water. For example, if you set it to heat during morning shower time (6:00-8:00) and evening bath time (18:00-22:00), you will be able to get hot water when you need it. Also, if you suddenly need hot water, you can manually heat it up by pressing the "reheat button."
- Q: Will the image quality deteriorate when using the Aestiquo P1's Eco mode?
- A: Eco mode reduces the brightness to 70%, so it may seem a little dark when used in a bright room, but in a dark room (when used as a home theater), you will hardly notice any degradation in image quality. In fact, reducing the brightness may actually improve the contrast of the screen relatively, making it easier to see fine details in dark areas. When using in a bright room, you can turn off Eco mode and adjust the brightness.
- Q: Is there any other way to reduce standby power consumption than unplugging the device every time?
- A: Using a power strip with a main switch eliminates the need to unplug appliances. For example, you can connect a TV, DVD player, and game console to one power strip and then simply turn off the power strip's main switch when they're not in use, reducing the standby power consumption of multiple appliances at once. Smart power strips also allow you to remotely turn the power on and off from a smartphone app, making them even more convenient.
- Q: Will filling up my refrigerator increase its energy consumption?
- A: Filling your refrigerator moderately may actually help reduce electricity consumption. The air inside the refrigerator heats up easily, so if there is not much food inside, outside air will flow in when you open the door, increasing the amount of electricity needed for cooling. However, if you pack food too tightly, the air inside the refrigerator will not circulate well and cooling will be uneven, so make sure to leave a moderate amount of space.
If you have any questions about the Aestiquo P1 projector's power saving features or power saving measures, please contact the support desk listed below.
・Aestiquo official support: Inquiry form
・Telephone support: 050-5050-9599 (Tuesday to Friday 10:00 to 18:00)
・Product purchase: Aestiquo P1 Projector official website
・Reference for energy saving information: Ministry of Economy, Trade and Industry, Home Energy Saving Guide
