Renewable energy is great. It helps the environment, lowers energy bills, and provides reliable power when you need it. Before getting solar solutions or other renewable energy systems, first do your research. It would help if you audited your energy needs.

 What is an energy audit?

An energy audit checks your home or business energy use over a period, like a typical day usage. An energy audit helps find out:

• How much power do you need?
• How much renewable energy can you make and keep based on your proposed solution?

Why do you need an energy audit?

How do you know what kind of renewable energy system you need? How do you know how much electricity it can generate and store? How do you know what appliances it can power and for how long? That's where your appliances' power rating and energy consumption come in. By knowing these numbers, you can:

•     Pick the correct parts for your renewable energy system. This includes solar panels, batteries, and inverters.
•     Know the capacity of the system you are building, what it can or can't do, how long it will work, etc.
•     Save money on a system that is too big or not waste money on a system that is too small for your needs.

For example, if you need 3,000 watts for 12 hours, your system must make and store that much power. It's like a small generator unable to run your fridge or washing machine. But this is renewable energy, and you may need to learn more about it. So you want to avoid buying the equivalent of a 0.5kva generator when you want to power a shop. On the other hand, you don’t want to spend money on a 50 kva generator to put on a few fans. You must know your appliance power use to build the right renewable system.

 How to do an energy audit?

You need to know how much energy your appliances use to save money on electricity bills. Energy is measured in watts, which tells how much power an appliance needs. Some appliances, like kettles, have their power ratings marked on them. For example, you can buy a 1500-watt kettle, a 2000-watt kettle, or a 300-watt kettle. But what about other appliances that don’t have their power ratings displayed? How can you find out how many watts they use? That's where an energy audit tells you exactly how many watts each appliance needs. There are different ways to do an energy audit, depending on how accurate and detailed you want it to be. Here are some options:

Look at the label.

The easiest way to determine how much energy your appliances use is to look at the label. Most appliances have a label that shows their power rating in watts (W) or kilowatts (kW). This is the amount of energy they consume per hour of operation. For example, a 1500 W hair dryer uses 1500 W energy in half an hour.

The label that shows your appliances' power rating can be located in different places. You can find this information on the appliance, packaging, or manual. Look for a label with sections like "Rated" or "Input" showing the wattage (W).

For example, a water pump label might show:

• Rated: Input 750W Current 3.5A
• Max: Input 900W Current 4.2A

The "Rated" wattage is what the appliance typically uses.

This is an example of a label from a water pump. It shows the power input and current for the Rated and Max modes. The Rated mode is the normal operating mode of the appliance. The Max mode is the highest operating level. The power input is measured in watts (W), and the current is measured in amperage (A). The label shows the water pump's average use power is 750 watts. It also shows the maximum power is 900 watts. At its highest level, the pump uses 900 watts of electricity. You will use this number to calculate your energy consumption and cost.

The current level is also significant, but there are other matters to attend to now. It's essential to write down the numbers. This will help you choose the correct parts for your system later. But leave that for now.

Search on the manufacturer's website.

If the label on your appliance is missing or misplaced, you can look for the information online. You can visit the maker's website or a sales page to find the specifications or specs section. You are searching for the power input ratings in watts and amps. 

Use an energy meter.

An energy meter shows you how much power any device you plug into uses. This is the best way to see the actual energy use of your appliances at home. You can use the meter to compare appliances, see the most efficient ones, and track your energy use. It helps you save money and the environment. You can measure each appliance or a group of appliances. You can also track how long you use each one and calculate the total energy used daily.

 How do you use the information from your energy audit?

Before switching to renewable energy, you must understand your power use and costs. Start by doing an energy audit. This means listing all the appliances and devices you use and writing down how much energy each uses. You can find these ratings on the labels or manuals or use a power meter to measure them.

But you need more than the energy ratings to tell you how much energy you use. Consider how long and how often you use each appliance and how efficient they are. It would help if you did some math to calculate your energy consumption and cost. But don't worry, you don't have to do it manually. Many tools can do it for you. With this information, you can design a renewable energy system to meet your needs and save money. 

Conclusion

An energy audit is a crucial step in your renewable energy journey. It helps you understand how much energy you use. This is important when planning your renewable energy system. It ensures you get the right size system for your needs, avoiding wasting money on one that's too big or too small. This also helps you maximise energy efficiency and savings.