How to think about and measure the energy use of your home sound system.
As energy costs continue to spiral, cost-conscious consumers need to manage their energy consumption. While electricity requirements vary, a typical home sound system will use 20 to 50 watts in standby mode, increasing to 200 watts at maximum volume. But many setups aren’t typical, so how do you assess your own?
Basic audio components such as turntables and CD players draw minimal power, but there’s a direct connection between playback volume and energy consumption; the louder you go, the more energy it requires. Audiophiles using esoteric combinations of state-of-the-art equipment and vintage analog tech (particularly amplifiers) may find their system costs more to run. Similarly, independently powered speakers inherently use more energy than those drawing power directly from the amp, and large home theatre systems tend to consume even more energy.
It’s also true that leaving any battery-powered components of your system plugged in can degrade the power cells over time, though most modern streaming speakers are designed for this. USB chargers also draw power when plugged in even in standby mode, which adds up across your home.
Measuring your energy consumption
To measure your own setup, first list its components and identify the wattage and average daily use for each item. You may need to consult product manuals and manufacturer websites for this information but you can also measure actual power draw using an inexpensive watt meter. These plug into your wall socket to act as an intermediary between your kit and the energy supply to measure actual energy consumption. To achieve a realistic range, take readings at both high and low volumes since energy requirements are higher at high volume.
You should also measure standby energy consumption — energy used when the device is not being used but is also not switched off. Most modern devices typically have a low-power standby mode, but older equipment doesn’t and may draw significant power even if idle, though it does vary.
Smart plugs are possibly the best investment you can make to manage power consumption from your home sound system or any other electronic system in your home. They provide accurate energy data and allow you to switch devices off remotely to eliminate any standby power draw.
Calculating energy costs
Once you have the wattage for each item in your system, you can use an online power calculator to figure out likely cost, or use the following formula:
Daily energy (kWh): Wattage x Time (hours), divided by 1,000.
Monthly cost: [Daily kWh x Days per month] x Cost per kWh.
For example, a 100-watt amplifier used for five hours a day across 30 days consumes 15 kWh per month, following the above formula:
- Daily energy: Power 100 watts x 5 hours = 500 watt hours.
- kWh, achieved by dividing above by 1,000 = 0.5 kWh per day.
- Multiplied by 30 days = 15 kWh per month.
According to Federal Reserve data, that’s $2.94 per month at current U.S. cost ($0.196 per kWh). It means a 100-watt amplifier is costing you nearly $36 each year to run, so about the price of a couple of lattes, a nice lunch, or four months of a Netflix subscription. Your personal setup will vary, but this formula works anywhere; not only will it empower you to assess the energy cost for your home sound system, but it will also help you understand the energy consumption of any other electrical devices you use in your home, like smart bulbs versus LED bulbs.
