British Thermal Unit
(BTU)
Description
Energy is something we use every day – whether by turning on a light, preparing food, heating water, or air conditioning. So how do you figure out just how much energy you’re using—especially when it comes to heating or cooling? Enter the British Thermal Unit, aka, BTU
Let’s get into what a BTU is, and why it’s important, and where do we use it in our everyday lives in this article.
What is a BTU?
It’s only a unit of measuring heat. More specifically, the amount of energy needed to raise the temperature of one pound of water through one degree Fahrenheit.
We can use a single example to explain this:
Think of a glass of ice water. It takes only a bit of energy to warm it up slightly, by only one degree. That little bit of energy is one BTU. It really isn’t all that much, but when you’re heating or cooling very large spaces, all those BTUs really start to add up.
BTU is vital because it helps us determine the energy that heating and cooling systems consume. It includes heaters, air conditioners, furnaces, and even grills. Usually, you can find the BTU rating on the rating label of a room air conditioner or a gas heater. It tells you how powerful that unit is. The higher the BTU number, the more heat the appliance can generate or remove.
In which field is the application of BTU?
Some of the common places where BTU is employed include air conditioners, from where you can be able to tell how good an air conditioner is by the number of BTUs it can take out of a room within an hour, for example: a 5000 BTU air conditioner is suitable for a small bedroom. - 12000 BTU for a medium-sized living room. The bad rating will ensure that your room cools down without wasting energy.
Agreed the rating of heaters in BTUs. For instance a gas furnace or water heater with a high BTU rating would provide fast and efficient heating.
Example:
Such a heating system must have capacity so that it can deliver 100,000 BTUs or more to sufficiently warm bigger houses.
1. Cooking Appliances
Some of the ranges and cooktops in the kitchen reveal their BTU ratings. This shows how hot they may become. The higher the BTU, the quicker the food will cook.
2. Application of Natural Gas and Fuel Measured
while using natural gas in terms of BTUs or therms. One therm is equivalent to 100,000 BTUs.
How BTU Relates to Other Units
Mostly used in the United States, BTUs are not the only unit of measurement; other countries use joules or kilowatt-hours.
Conversion between Energy Units:
- 1 BTU ≈ 1,055 joules
- 1 kWh ≈ 3,412 BTUs
So a ”normal” 1,500-watt electric heater (which translates to 1.5 kWh used in an hour) produces roughly the equivalent of 5,118 BTUs of heat per hour.
How to Pick the Right BTU for Your Needs
You have to be sure to get the right BTU rating when purchasing an air conditioner or heater. Without enough BTUs, the unit will not be powerful enough, but too many can waste energy. A general rule follows for room size concerning BTU:
Size of the room (in square feet) | Recommended BTUs
Up to 150 — 5,000
150–250 — 6,000
250–350 — 8,000
350–450 — 10,000
450–550 — 12,000
550–700 — 14,000
These numbers will vary depending on factors such as:
• Insulation in the room
• Windows
• Height of the ceiling
• Number of windows
• Your local weather
Fun Fact: the British Thermal Unit comes originally from
The British Thermal Unit (BTU) was developed in the 1800s in Great Britain. Great Britain has turned metric today, but still, the unit is very much alive in both the U.S. and Canada, particularly related to HVAC systems.
You might think the British Thermal Unit sounds too technical to comprehend but really, it’s just a good way to measure how much heat energy is being used, generated, or removed. So, if you are in the market for a heater, an air conditioner, or a grill, the more BTUs you know it has, the better and more energy-efficient choice that can be made.
This is how you can be warm, save money, and be smart about energy.