Estimate a refrigerator's monthly electricity cost as "labeled annual consumption ÷ 12 × price per kWh", and do not multiply the nameplate wattage by 24 hours. For example, a refrigerator labeled 300 kWh (度) per year uses about 25 kWh a month; using the average residential electricity price of NT$2.77 per kWh mentioned in the Ministry of Economic Affairs press release of 2025-09-19 (an assumed value; that press release also announced a price increase at the same time, and this article did not check whether it took effect), that comes to about NT$69. The annual consumption is printed on the energy efficiency grade label (能源效率分級標示) (stuck on the front of the unit or attached to the manual, as announced), and it is the figure the manufacturer labels based on its registered data. This article sets out the formula, how to read the label, calculations from two manufacturer spec pages, and how to work out whether replacing an old refrigerator pays off, and every electricity price is stated to be an assumed value.
Why you cannot multiply nameplate watts by 24 hours
Many people who want to estimate refrigerator electricity cost look at the "rated power" on the nameplate, multiply by 24 hours, and then by 30 days. This method tends to overestimate, because the compressor does not necessarily run all day: it stops when the temperature inside reaches the set value and starts again when the temperature rises. Actual consumption is "running time × power", and the nameplate does not tell you what share of the day is running time. This is a general principle, not a quote from a source, and no figure for "how much of the time it runs" is given.
Also, nameplate power is not the same as labeled energy consumption. The grading label system of the Energy Administration, Ministry of Economic Affairs (能源署) requires manufacturers to register a tested energy factor value and annual consumption, and these are the figures to compare when comparing different refrigerators. LG Taiwan's buying-guide page also says that the labeled annual consumption is in "kilowatt-hours (kWh) per year", from which you can estimate the electricity used by a refrigerator running 24 hours a day for a year. In other words, the annual consumption is already the full-year electricity use, and you do not need to multiply it by any number of hours.
How to read the annual consumption, energy factor and grade on the label
According to the fields of Appendix Table 3 (附表三, the registration application form) of the Ministry of Economic Affairs notice on permitted energy consumption standards and energy efficiency grade labeling items, methods and inspection for refrigerators (電冰箱容許耗用能源基準與能源效率分級標示事項、方法及檢查方式), the "energy efficiency grade label content" in Appendix Table 3 (the registration application form) includes the following items, which the manufacturer fills in when registering:
- Product model
- Effective volume (liters)
- Energy factor value (liters per kWh per month)
- Energy efficiency grade
- Annual consumption (kWh per year)
- The announcement year and document number of the refrigerator energy efficiency grading standard table it is based on
As for how annual consumption is calculated, the note to the current Appendix Table 3 reads: "annual consumption (kWh) is calculated as labeled monthly consumption (kWh per month) × 12 months, with annual consumption rounded to the nearest whole number"; the 2012 version of the announcement on the "related provisions" page of the Energy Administration has the same wording ("annual consumption (kWh per year) is calculated as labeled monthly consumption (kWh per month) × 12 months"). So the "annual consumption" on the label is "monthly consumption × 12", and to estimate the monthly electricity cost you simply divide by 12 the other way round.
Energy factor (EF) is not electricity consumption
The Energy Administration's energy-saving comparison page (節能比一比) for refrigerators explains the energy factor like this: refrigerator efficiency is expressed as the energy factor (EF, Energy Factor), in liters per kWh per month, that is, the volume that can be used per 1 kWh consumed each month; the higher the EF value, the more energy-saving. The bigger this number the better, which is the opposite direction from "annual consumption" (the smaller the annual consumption, the more energy-saving).
Note that the standards table in the announcement is calculated using "equivalent volume": the effective volume of the refrigerating compartment plus the effective volume of the freezer compartment multiplied by a conversion factor, and the factor depends on the star rating of the freezer compartment. So you cannot directly check EF by "effective volume ÷ monthly consumption". The spec pages of the two LG models below show the difference.
Grades 1 to 5: the smaller the number, the more energy-saving
The banner text on the Energy Administration's energy efficiency grade label management system page reads "the smaller the energy efficiency label grade, the more energy-saving", and LG Taiwan's page also says refrigerator energy efficiency is divided into grades 1 to 5, with grade 1 the most energy-saving. Be careful, though: the grading standards table gets amended. The label has a field for "the announcement year and document number of the grading standards table it is based on", and the standards table gets amended (for example, in 2025 an announcement amended point 5 and Appendix Table 5 (附表五)), so the thresholds of different versions may differ, and comparing grades is only fair between labels based on the same version of the standard.
How to calculate one month's electricity cost: the formula and worked examples
The formula has only three steps:
- Monthly consumption (kWh) = labeled annual consumption ÷ 12; if the spec page lists only monthly consumption, use it directly.
- Monthly cost (NT$) = monthly consumption × price per kWh.
- Annual cost (NT$) = labeled annual consumption × price per kWh.
Assumed price per kWh
The Ministry of Economic Affairs electricity price review committee press release of 2025-09-19 says: "the current average residential electricity price is NT$2.77 per kWh". The same press release describes tiered increases for residential use by consumption (NT$0.1 more per kWh for 700 kWh or less, NT$0.2 more per kWh for 701 to 1,000 kWh, and NT$0.4 more per kWh for 1,001 kWh or more), and the page does not give an effective date. The press release list in the Energy Administration's electricity price disclosure section shows that the review committee's resolution of 2026-03-27 was "no electricity price adjustment", and that its resolution of 2026-09-18 was "no decision on this electricity price adjustment for now". Note that NT$2.77 per kWh is the average before that adjustment, and the same press release announced increases for each tier at the same time. So the calculations below first assume NT$2.77 per kWh, checked on 2026-11-07; it is an average, not your actual unit price. Residential electricity is billed in tiers, and the more you use, the higher the unit price applying to the extra kWh, so please replace it with the unit price on your electricity bill, or enter your own numbers in the home appliance electricity cost calculator.
Monthly cost comparison for different annual consumption
| Labeled annual consumption (kWh per year) | Monthly consumption (kWh) | Monthly cost (NT$, at NT$2.77 per kWh) | Annual cost (NT$, at NT$2.77 per kWh) |
|---|
| 200 | 16.7 | 46.2 | 554 |
| 300 | 25.0 | 69.3 | 831 |
| 400 | 33.3 | 92.3 | 1,108 |
| 500 | 41.7 | 115.4 | 1,385 |
| 600 | 50.0 | 138.5 | 1,662 |
The amounts in the table are rounded results and are only arithmetic; they do not include the basic charge, other appliances or the effect of billing tiers.
Two manufacturer spec pages as worked examples
Below are LG Taiwan website spec pages checked on 2026-11-07. Only the numbers on the pages are cited, and this is not a recommendation. These two pages list "power consumption (kW.h per month)" and "EF value", and list neither annual consumption nor a grade, so the annual consumption was calculated by this article from "month × 12" in the previous section; the actual figure follows the label on the unit.
| Model (spec page) | Total capacity (liters) | Power consumption on page (kWh per month) | EF value on page | Month × 12 (kWh per year) | Monthly cost (NT$, at NT$2.77 per kWh) | Annual cost (NT$, at NT$2.77 per kWh) |
|---|
| GR-RL40SV | 377 | 18 | 20.9 | 216 | 49.9 | 598 |
| GR-LL84S | 736 | 47 | 20.5 | 564 | 130.2 | 1,562 |
The two are different types: the page title of GR-RL40SV is "direct-drive inverter single-door refrigerator" and that of GR-LL84S is "direct-drive inverter 對開 refrigerator", so you cannot compare by capacity alone. The capacity is roughly double, while monthly consumption differs by more than 2.6 times. Another reminder: 736 ÷ 47 is about 15.7, which does not match the EF value of 20.5 on the page, because the EF in the announcement is calculated with the equivalent volume (the freezer volume is multiplied by a conversion factor), so you cannot divide the capacity directly. When comparing refrigerators, compare the "annual consumption" of the same type and same capacity directly.
The monthly consumption listed on the spec pages is a whole number, while the true labeled value may have decimals, so the annual consumption and costs in the table above are only estimates.
Labeled values versus actual electricity use
The labeled value is a figure the manufacturer registers based on a test report. The announcement provides that the measured value of the energy factor may not be lower than the standard value, and must be at least 95 percent of the labeled value of the product; the competent authority may also run spot tests each year, and if a spot test result does not reach at least 95 percent of the labeled value, the manufacturer is notified to retest. This means the labeled value has a checking mechanism, but it is a figure obtained under fixed test conditions and does not equal the actual electricity use in your home.
LG Taiwan's page puts it very directly: "power consumption will differ depending on how you use it, how often it is actually opened and the operating environment of the refrigerator". As for the ambient temperature, set temperature and other conditions used for label testing, this article gives no numbers. What you can do is treat the labeled annual consumption as a basis for "comparing different models under the same conditions", and confirm the actual electricity cost by measuring over a period with a plug-in electricity meter (插座式電表).
The on-site refrigerator and freezer temperature setting guide covers the common factors affecting actual electricity use from the settings side; this article does not give percentages such as "opening the door more uses more by a noticeable share" (多耗幾成).
Will replacing an old refrigerator pay off
The payback calculation puts the "electricity cost saved" next to the "net outlay for replacement":
- Annual electricity saving (NT$) = (annual kWh of the old unit − labeled annual consumption of the new unit) × price per kWh.
- Net replacement outlay (NT$) = purchase price of the new unit − residual value or trade-in credit for the old unit − subsidies and tax refunds.
- Payback years = net replacement outlay ÷ annual electricity saving.
The annual kWh of the old unit cannot be estimated by sayings such as "old refrigerators use more by a noticeable share" (多耗幾成), because there is no official figure to cite; a more reliable way is to read the label on the old unit, or to measure it with a plug-in electricity meter. Below, an assumed net outlay of NT$20,000 (only to demonstrate the calculation, not the price of any product) and NT$2.77 per kWh are used to show the payback years for different annual kWh saved:
| kWh saved per year | Annual electricity saving (NT$) | Payback years (net outlay NT$20,000) |
|---|
| 100 | 277 | 72.2 |
| 200 | 554 | 36.1 |
| 300 | 831 | 24.1 |
| 400 | 1,108 | 18.1 |
The arithmetic shows that on the electricity difference alone, replacement takes many years to pay back, unless the net outlay is very low or the kWh saved are very many. More practical considerations are usually that the old unit already breaks down often, does not cool enough, or has repair costs that are a large part of the net outlay. When the refrigerator runs but does not cool, you can first follow the order of checks for a refrigerator that runs but is not cold to rule out causes you can handle yourself, and then decide whether to repair or replace.
Subsidies and tax refunds
The amounts and application deadlines of subsidies and tax refunds for energy-saving appliances change, so this article does not copy the numbers again. Please read the on-site summary directly: energy-saving appliance subsidies and tax refunds summary, and follow the competent authority's latest announcements.
What to watch for under the new standard from 2027
The related provisions page of the Energy Administration's energy efficiency grade label management system lists an announcement of the Ministry of Economic Affairs dated 19 May 2025 (document no. 經能字第 11458002070 號) that amends parts of the notice on permitted energy consumption standards and energy efficiency grade labeling items, methods and inspection for refrigerators, and point 5, Appendix Table 5, taking effect on 1 January 2027 (中華民國 116 年 1 月 1 日, that is, the year 2027); the current provisions are the version issued on 10 May 2017 and effective on 1 January 2018. In practice this means: from 2027, the grade thresholds for labels newly registered or under the new version of the standard may differ from the labels on the market now. The thresholds of the new Appendix Table 5 are outside the scope of this article, so it does not compare the old and new grades; it only reminds you to look at "the announcement year and document number of the standards table it is based on" on the label.
Frequently asked questions
How many kWh does a refrigerator use in a day?
Divide the labeled annual consumption by 365 to get the average kWh per day; for example, a label of 300 kWh per year averages about 0.82 kWh per day. This is only an average, and actual use will go up and down with the season, how often the door is opened and where the unit is placed.
Can the EF value be used to work out electricity consumption directly?
Not recommended. The EF value is calculated with equivalent volume, and the freezer volume is multiplied by a conversion factor, so "effective volume ÷ EF" will not exactly equal monthly consumption. Looking directly at the labeled annual consumption is the most accurate.
How do I estimate the electricity cost of a refrigerator in a rental?
First look at the energy efficiency grade label on the unit and find the "annual consumption"; if the label has faded, you can measure over a period with a plug-in electricity meter and multiply by the unit price on your electricity bill. If the label on an old refrigerator provided by the landlord is unclear, you can also look up the model in the dataset "refrigerator energy efficiency grade label registration information" published by the Energy Administration on the government open data platform (政府資料開放平台).
Is a grade 1 always more energy-saving than a grade 2?
Usually, when compared under the same version of the standard, of the same type and the same capacity; the thresholds in standards tables of different years differ, and a large-capacity model, even with a high grade, may still have higher annual consumption than a small-capacity model with a lower grade. When comparing, look at both the grade and the annual consumption.
On my electricity bill, how can I tell how much is the refrigerator?
The bill only shows kWh for the whole household, not for a single appliance. A more workable way is to measure the refrigerator over a period with a plug-in electricity meter and then convert it to monthly kWh with the formula above; you can also use the labeled annual consumption as a reference, and when the two differ a lot, check the placement, the door seal and the set temperature.
Sources
- Energy Administration, Ministry of Economic Affairs, energy efficiency grade label management system: related provisions (2012 announcement page, checked 2026-11-07, in Chinese): the 2012 version of the announcement likewise states annual consumption = labeled consumption (kWh per month) × 12 months (historical comparison).
- Energy Administration, Ministry of Economic Affairs, energy efficiency grade label management system: list of related provisions, page 2 (checked 2026-11-07, in Chinese): the current version (issued 10 May 2017, effective 1 January 2018) and the amendment announced 19 May 2025, effective 1 January 2027.
- Ministry of Economic Affairs announcement: permitted energy consumption standards and energy efficiency grade labeling items, methods and inspection for refrigerators (checked 2026-11-07, in Chinese): the annual consumption calculation in Appendix Table 3 (month × 12, rounded to a whole number) and the label content fields, the measured energy factor value having to reach 95 percent of the labeled value, annual spot tests, and the definition of equivalent volume.
- Energy Administration, Ministry of Economic Affairs, energy-saving comparison: refrigerator comparison (checked 2026-11-07, in Chinese): the definition and unit of the energy factor (EF).
- Energy Administration, Ministry of Economic Affairs, energy efficiency grade label management system home page (checked 2026-11-07, in Chinese): "the smaller the energy efficiency label grade, the more energy-saving".
- Ministry of Economic Affairs electricity price and rate review disclosure section: press release of 2025-09-19 (checked 2026-11-07, in Chinese): average residential electricity price of NT$2.77 per kWh and the description of tiered increases.
- Ministry of Economic Affairs electricity price and rate review disclosure section: press release list (checked 2026-11-07, in Chinese): headlines of the review committee results of 2026-03-27 and 2026-09-18.
- Government open data platform: refrigerator energy efficiency grade label registration information (checked 2026-11-07, in Chinese): a registration dataset published by the Energy Administration, updated irregularly.
- LG Taiwan: how to choose an energy-saving refrigerator (checked 2026-11-07, in Chinese): the meaning of annual consumption, grades 1 to 5, and actual consumption varying with usage and environment.
- LG Taiwan: GR-RL40SV spec page (checked 2026-11-07, in Chinese): total capacity 377 liters, consumption 18 kWh per month, EF value 20.9.
- LG Taiwan: GR-LL84S spec page (checked 2026-11-07, in Chinese): total capacity 736 liters, refrigerating compartment 476, freezer 260, consumption 47 kWh per month, EF value 20.5.
