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Once you get into the basics of how electricity functions, it won’t be long until you need to understand volts and watts.
If you want to learn more about electricity besides just how to plug into a wall socket, understanding what volts and watts measure and how they’re interconnected is essential.
This beginner’s guide tells you everything you need to know about watts and volts, how they relate to your electricity consumption, and how much you need to power your appliances.
We’ll also examine why they’re even more crucial to understand if you’re considering backing up your home in a power outage or switching to clean, renewable solar.
Let’s begin!
What Is a Volt?
A volt is a unit of electrical potential difference that measures the amount of power transferred per unit of charge flowing through a circuit. Volts are commonly referred to in the plural as voltage and abbreviated as the letter V.
You’ve probably encountered the term voltage as a measure of the electricity a wall socket provides. For example, in North America, the standard voltage for household electricity is 120V, though some energy-hungry appliances and HVAC systems may require 240V.
Mains electricity voltage varies significantly by country. In the UK, the standard voltage is 230V instead of 120V.
Plug shapes vary from country to country too, but it’s crucial to understand that many appliances can’t just be plugged into a travel adapter. Your smartphone or laptop should be OK. A hairdryer? Maybe not.
In simpler terms, consider voltage a measure of the pressure pushing electrons — the carriers of electricity — through a circuit. Similar to water pressure through a hose.
What Is a Watt?
A watt, abbreviated as W, is the unit for measuring the rate of energy transferred over time. One watt is equal to one joule of energy transferred per second.
In layperson’s terms, watts (or wattage) measure how much electricity a device requires to start and run and how much a power source — such as a solar generator — can output at any given moment.
Watts is the most commonly used unit to measure electricity. For one thing, unless you’re living off-grid, you’ll see them on your electricity bill every month. The electricity you consume is measured in watt-hours (Wh) and kilowatt-hours (kWh).
Wattage measures how much electricity an appliance consumes. Watt-hours measure how much electricity an appliance (or household) consumes over time.
For example, if you have a 700W refrigerator operating 24 hours a day, its daily electricity consumption is 16.8 kWh.
Watt-hours = Operating Wattage x Hours of Operation
If you only have the time to invest in understanding one concept in electricity, watts, and watt-hours are the best place to start.
What Are the Differences Between Volts and Watts?
Volts and watts are both essential metrics in electricity. They’re interrelated but measure very different things. Voltage indicates electrical potential or “pressure,” the force driving an electric current through a circuit. On the other hand, watts measure the electricity being produced or consumed.
Using the analogy of a hose:
- Volts are like water pressure
- Watts is the amount of water that flows
If your primary motivation for exploring the basics of electricity is a desire to generate power or monitor consumption, watts (and watt-hours) are the essential units to understand.
Why Are Electrical Ratings Important in Solar Power?
Electrical ratings, measured in volts and watts, are essential to evaluating solar power systems. Investing in a solar energy solution that doesn’t meet your voltage and wattage requirements can be a costly mistake.
For residential applications, you’ll want a portable power station or other balance of system that outputs electricity at 120V — that’s a given. If you’re planning on running high-wattage appliances and HVAC systems, you’ll probably want the option to output power at 240V too.
But when it comes to wattage (for measuring AC output) and watt-hours (for measuring solar battery storage), the variations are almost endless.
The right choice for you depends on your application, the wattage of the appliances you want to operate simultaneously, and how long you want them to run before recharging your solar battery (or batteries.)
Volts to Watts Conversion
Understanding how to convert volts to watts can help evaluate a solar power system or any type of generator or electrical device.
Here are the three most commonly used methods for converting voltage to wattage, with examples.
1. DC Volts to Watts
Direct current (DC) is a steady flow of electric charge in a single direction. For DC circuits, the formula to convert volts to watts is straightforward:
Watts (W) = Volts (V) × Amps (A)
For instance, a DC system operating at 12 volts and drawing 2 amperes will require 24 watts of power.
2. AC Single Phase Volts to Watts
Alternating Current (AC) flows back and forth rather than moving in one direction. It’s better known as household electricity.
For a single-phase AC circuit, the voltage-to-wattage conversion involves a metric known as the “power factor” (PF).
The formula is:
Watts (W) = Volts (V) × Amps (A) × Power Factor (PF)
The power factor is a number between 0 and 1, representing the efficiency of the power conversion.
For most home appliances, the PF is close to 1.
3. Volts to Watts using Resistance
In some instances, you might know a component’s resistance (measured in ohms) but not the current.
In such cases, Ohm’s Law and the power formula can be combined:
Watts (W) = Volts (V)2/Resistance (R)
For example, a component with a 4 ohms resistance operating at 12 volts would use 36 watts of power.
If you’re building a DIY solar power system, these conversions can be essential when gauging the efficiency and compatibility of different components in your solar power setup.
If you opt for a plug-and-play whole home generator solution, you’re unlikely ever to need them.
Volts to Watts Conversion Chart
The chart below is a cheat sheet for common conversions between volts and watts.
Use the formulas above if the conversion you need isn’t listed here.
| Volts (V) | Amps (A) | Watts (W) |
| 10 V | 1 A | 10 W |
| 20 V | 1 A | 20 W |
| 30 V | 1 A | 30 W |
| 40 V | 1 A | 40 W |
| 50 V | 1 A | 50 W |
Frequently Asked Questions
There is no such thing as the “number of volts in a watt.” The two units measure different (but related) components of electricity. A watt represents energy expended over time and can be calculated using volts and amps. Wattage can be determined by multiplying volts by amps in DC systems and considering the power factor in AC systems.
Final Thoughts
Understanding the relationship between volts and watts is foundational in electricity.
If you’re considering a switch to solar, understanding the basics of voltage and wattage — and common conversions — can help ensure functionality, compatibility, and safety.
EcoFlow’s plug-and-play solar power systems eliminate the heavy lifting of converting volts to watts for different applications.
All you need to determine is your total electricity output and consumption needs.
Check out our off-grid power solutions today to find your perfect fit.
With everything from portable solar panels for off-grid adventures to whole home generators, there’s a solution for virtually any off-grid power application at EcoFlow.