In this series, I’ll cover several important topics surrounding a power or energy budget. What they are, the benefits of having one (especially off grid), and how to create one. Finally the series will conclude with real measurements and an online form for you to get some ideas for yours budget and save energy! First we start of with the benefits.
Why a Power Budget?
If you want a quality power system the place to start is with a power budget. Your experience with an emergency power genverter, or your solar powered home will be one with less hassle and cost if you get this critical step right. A detailed power budget provides 3 immediate benefits when creating or operating your new system.
[editors note: The entire series can now be found on our new Power Budgets page for your convenience!]
- It determines the best initial component sizes. Understanding that the system will grow in time and armed with a power budget, arms you to “future proof” the initial design. For example, getting a larger inverter initially, so it doesn’t need to be replaced when upgrading your battery bank or increasing your power needs.
- It sets your expectations. Nothing worse than moving to your off grid home and finding out that you can’t operate your <favorite appliance> as long as you like! Knowing what are the large loads on your remote power system can help make those critical first design choices better.
- It allows smart system operation. Day to day operation of your remote power system will be improved with your understanding of how much battery power is stored on those cloudy, windless days.
You will want to design in good battery monitor meters. Like our Tri-metric battery monitor, it records AH(amp hours) in and out, giving you a good idea of your battery bank charge at any time. This is critical for smart operation, and we look at ours several times a day!
One fun exception to living within your power budget is Free Power Time.
How do you go about creating this power budget? How much power does it take to make Espresso? or run my TV? Good question. The crude way to get a guestimate of the power required by your favorite appliances is to look at the UL power requirements on the packaging or device. Be warned this is often twice the actual power consumption, since it is the maximum power that will ever be used, even when the appliance is failing. Remember Underwriters Lab is a safety organization.
The best way to get a real world number is to measure it. Before we moved 10+ years ago, there were not any inexpensive AC meters to measure power. We measured appliances with our Tri-Metric meter after we moved. You, however, have the opportunity to benefit from the emerging ‘green’ industry and can get a small inexpensive device, P4400 “Kill a Watt Monitor“, that will measure the real power of anything you plug into it! At about $20 each, I just ordered two to compare with the Tri-Metric battery monitor!
With the P4400, there is a whole new way to create an accurate budget with real world numbers. Heck, even living on the grid, this could be very useful in helping increase your “power consciousness” and save some money too.
Next time we’ll go over how power budgets are calculated, and how they affect your power bill or your remote power system performance.
Continue to part 2: Power Budgets : Simple Calcluations Fast
Do you have a power budget for your power system? Did you create it before or after your move? Planning on and off grid move? Please share your insights and questions with a comment below!