Energy Monitoring

Topic 3: Energy Monitoring


Energy monitors are small devices that help you discover how much energy you’re using in your home or business, how much it’s costing, and the associated Carbon Dioxide (CO2).  It will also show you how much energy and money you’re saving when you change the way you’re using energy. OWL energy monitors are one of many types of energy monitors available.

This topic will include how to use your OWL Energy Monitor, how to use it to learn about your electricity consumption, and assess your energy savings, how to set targets, and how to download your energy data (OWL + USB only).

Your OWL energy monitor can give you a real-time estimate of the electricity you are using. Using the OWL won’t cut your electricity bills on its own, but can help make you aware of how much you’re using, and how much you can save. According to the Energy Saving Trust, using an energy monitor can contribute to you reducing your electricity consumption by between 5% and 15% in the first year of use.

Note: Energy monitors should not be confused with Smart meters, which are a new type of electricity meter which are being rolled out nationwide. They send information about your usage automatically to your energy supplier leading to more accurate bills. You can find out further information about smart meters here:

What type of OWL do you have?

There are three types of OWL installed on the Islands. Most businesses have an OWL Intuition, but some people who either do not have WIFI, or the meter was too far from the router, will have one of two types of non-wifi OWL installed. Below is a quick guide to help you work out which OWL you have.


OWL Micro+

Data available via digital display.  

Data available by viewing on the display or downloading it from the display unit via USB connection.

The data can then be viewed using software obtained from the OWL website.

OWL Intuition

Data available via web portal only.

The receiver (pictured to the right) is plugged into the back of your router allowing you to access the data online.

The OWL Intuition-e is for single phase meters, and the Intuition-lc is for 3 phase meters.


Detailed manuals and operating instructions can be obtained from the main OWL website or from the links page on this website. If you have a problem or a query then you can contact either Ben Robbins who will pass it to us, or you can contact us directly via, or you can use the help desk and FAQs on the OWL website.  For quick troubleshooting assistance, refer to the troubleshooting guide provided during your survey.

All OWLs operate by collecting electricity data from the clamp-on CT (current transformer) sensor. This sensor clips around the cables coming into your meter and reads the flow of electricity in order to work out the consumption. They take a reading every few seconds. Because the sensors are not reading the meter, they are reading the flow into the meter, if the signal drops out for some reason or the data collection is not continuous, then the total consumption for that period will appear lower than it really was.

These sensors connect into a small transmitter which transmits the data to your OWL unit or to your receiver plugged into your router, depending on  the type of OWL you have.

Quick Guides

Here are some quick guides to using the different OWLs. Its a good idea to spend time learning the way round your OWL so that you don’t always need to refer to the manual in future.

OWL Micro+

Here is a picture explaining the layout of the display screen.

You will need to re-pair your sensors and your OWL and set it up again if you change the batteries, so it helps to know how to do this.

Set Up

Make sure you have a small paperclip, and details of your current electricity tariff to hand before you start.

    • Follow the instructions in the manual to ensure correct installation of the sensor and to connect the sensor to the transmitter.
    • Next you need to pair the transmitter to the display. You will need a small pin or paperclip for this bit.
    • Use the end of a paperclip to press the RESET button in the back of the battery compartment of the transmitter.
    • Press and hold the check button until the red LED on the front starts flashing. The transmitter is now in CHECK mode.
    • Take the end of a paperclip and press the RESET button in the back of the display unit.
    • Next you need to enter the correct time and date on the front of the display.
    • Have your electricity bill to hand for this one. Insert current cost of electricity per unit (Kilo watt hour, or kWh), by selecting MODE to select COST or ENERGY display. Entering your tariff will ensure you get as accurate cost reading as possible, at that moment. 
    • Once it is set up, you can choose the screen views, for real time and accumulative according to electricity consumption (in kW and kWh), cost (in £), Greenhouse gas emissions, average consumption (Day, Week or month), or comparative / historical consumption.
    • Use the comparison button on the OWL Micro to compare your electricity consumption before and after you apply some energy saving measures.
    • The OWL micro+ shows electricity consumption in Watts (W). A laptop will use around 100W depending on what you are using it for, whilst an electric shower may use between 5,000 – 8,000 W (5-8 kW).


The image below comes from the OWL+USB manual 

Ensuring it is set up correctly:

Follow the instructions in the manual to ensure correct installation of the sensor, connect the sensor to the transmitter, and pair the transmitter to the display. Make sure you have a paperclip to hand so you can use the end of it to press the RESET buttons.


  • Ensure you set the correct time and date (steps 1-5 in the installation and programming guide)
  • Have your electricity bill to hand to set your electricity tariff (or multiple tariffs if you have more than one), and follow instructions on step 3c of the installation and programming guide. This will ensure you get as accurate cost reading as possible.

Your display is divided into three screens, the ‘Real time data’ screen (top), the ‘Time, date and room temperature’ (bottom left), and the ‘accumulated average data screen’ (bottom right).

Reading Your Data

Your Display unit can show current consumption in either cost, energy or greenhouse gas emissions. The displays shows the current. To cycle between these options press MODE.

If you want to see your average consumption then simply press and hold the  ADJUST key and AVERAGE data will appear in the bottom right-hand corner.

AVERAGE DAY (based on 30 days rolling) will appear first. Press adjust again and AVERAGE WEEK (based on 30 days rolling) will appear. Press ADJUST key again and AVERAGE MONTH (based on 30 days rolling) will appear.

To return to the real-time data display press ADJUST key and hold for 2 seconds until you hear a short beep.

Connecting to your computer

As the name suggests, the OWL + USB allows you to download your data and store it on your PC (not compatible with Macs).

You’ll need to download the latest software from the OWL website.

The software user guide can be downloaded here.

Once you have installed the software simply connect the mini-USB port of the monitor to the PC, and the last 30 days data (or number days data stored if less than 30 days) will automatically download to the OWL USB Connect2 database.

Make sure to download data every 30 days or the data will be lost. You will still be able to view historic average data via the display but you will not be able to access more details data on your computer.

Using the software on your PC will then be able to access charts giving an overview of your usage. The example below is showing total daily consumption over a period of 1 month.

OWL Intuition (WIFI connected OWLs)

The OWL Intuition also has a transmitter but instead of a display unit it has a receiver that is plugged into the router in order to send data to OWL servers where it is accessed from the OWL website.

Re-Pairing Guide 

This guide is also available as a document, which you can access by downloading from this link.

If you have unplugged, switched off or moved your network OWL you might find that the signal is lost and / or you are no longer able to see your consumption on your online portal. It is likely you will need to re-pair the Network OWL and the OWL Transmitter (in your meter cupboard).

1  Hardware Check
First check your meter cupboard and make sure the 1, 2 or 3 white clamps are attached to your electricity supply and plugged into the OWL Transmitter.
If there are any clamps not fixed to a wire or loose please re-attach if you feel comfortable to do so. Then ensure your Network OWL (rectangular box with antennae) is connected to your wifi router or and has power supply. One of the LEDs on the Network OWL will flash with a triple green blip once the Network OWL has power and is connected to the OWL server (via connection to your router).

2  Log in to account
Head to Enter your Username and Password. Click “Login”.

3  Pairing Network Owl to Transmitter
Once logged into account the Owl Intuition Configuration Wizard should pop up automatically. If this does not happen click on Wizard in the toolbar at the top of the screen. Ensure that ‘Electricity / Solar Monitoring’ is selected on the configuration wizard and click ‘start’.


Is the Owl Transmitter already paired?
If the Owl Transmitter (the transmitter is installed in meter cupboard) is already paired with the
Network Owl you will see the below message:

Click ‘Next’ and move on. 

OWL Transmitter not paired?
If the Owl Transmitter is NOT already paired with the Network Owl you will see the below

Ensure CMR180 is selected and click ‘Next’. Follow instructions on screen to pair the devices. Click ‘Next’
If the transmitter and network owl have successfully paired you will see a successful pairing

For more guides about your OWL, head over to our links page.

Using Your OWL

Next lets look at ways to use your OWL in order to understand and reduce your energy use. Electricity use, being largely invisible, can be hard to keep track of. Energy monitors help to monitor it, visualise it and remind you to engage with it.

You will learn most about your electricity usage from an OWL if you use it to see how much electricity you use at different times of the day, and when you turn appliances on and off. Below we give some ideas to investigate your electricity usage. Warning: this can be addictive…but you’ll be in good company!

What’s your current consumption?

Familiarise yourself with the display to see how much electricity you are currently using, and your cumulative usage in the last day, week or month.

Your business’s ‘base load’. 

Baseload means the energy that the business or building uses all the time, unrelated to particular activity or temperatures. In short its the energy left over when you have turned off everything that could normally be turned off at the end of the businesses day.


In order to find out your baseload carry out the following activity. It’s best to do this in the daytime so that you can see what you are doing when you switch lights off! Go around and turn all the electrical appliances and lights off.  Your energy monitor will be showing the ‘base load’. This is unlikely to be zero, but what is your base load? Is it higher or lower than expected? Are there other appliances that are on which you may not have thought about (for example lights, burglar alarms or showers)?

Getting to know a ‘normal’ base load will help you spot any anomalies, which could alert you to potential electrical problems, and help you monitor your property in the winter and/or when your property is not in use.

Your property’s overnight load

Some businesses on the Isles of Scilly may not have any baseload once all lights, catering equipment etc is turned off. If you have tried the exercise above and your baseload is very low, next try understanding what a ‘best practice’ overnight consumption looks like for your business.

In the same way as above, imagine it’s the end of the day and go round the site turning off everything that does not have to be on. Fridges and freezers would be left on overnight but television boxes and microwaves could be turned off. If you have a wifi connected OWL don’t turn off your router overnight or you won’t be able to track your consumption!

Once you have turned off everything you can, make a note of the current consumption. That is what you are aiming to see every night.

Learning about your electricity consumption

Now try turning on different appliances, and seeing how much the reading on the Owl display rises. You will find that some of them make your consumption rise  dramatically, especially kettles, electric cookers and electric showers! Watch the Owl display as you switch your fridge and freezer on, and see what effect it has. Try turning on different types of light bulbs around the home and see the different levels of energy use. Turn your immersion heater on and see how much it uses. See how much electricity you are using for higher electricity usage appliances, such as washing machine / oven / tumble dryer.

Setting targets

Both OWL monitors allow you to set targets, and will warn you if consumption rises above your targets. You could set a target to reduce your usage. How about 5% of your current usage?

Comparing your consumption to your electricity bills

After you have been using the OWL for a month, compare your usage to your most recent bill, and your meter reading. Does your bill reflect your actual electricity consumption? If you don’t already, why not submit your utility meter readings to your electricity company so that you get more accurate electricity bills? Make sure to submit the meter reading from your actual utility meter, not your OWL.

Develop an OWL habit

Once you’ve become familiar with how your OWL works, and your electricity consumption, get into the habit of looking at it regularly, for example on a particular day each month. You can use it to think about and discuss how you can reduce usage even further.


If you’d like to use the OWL to do detailed monitoring, you can find some useful guides and template spreadsheets to download from the links below.

Appliance Monitoring Sheet

Guide to using the appliance monitoring sheet

If you want to post your results to the group, then head over to the forum to tell us what you found.


Paul at the Old Town Inn has been using his OWL to learn about the energy baseload at his business. He discovered that he could switch off his cooling systems overnight during the Winter which resulted in a significant saving.

He also discovered that the insulation inside his ice machine stopped the ice from melting overnight, and so he switches that off too.

By switching off many other appliances that were previously left on standby, and waiting till later in the morning before switching on cooking equipment in the kitchen, Paul is saving even more energy!

Barney from the Island Bakery on St Martins no longer turns on his oven before he needs to.

“I used to get in at about 4.30am and put the ovens onto 3, the maximum, to get them hot as soon as possible before turning them down to 2 when they were up to the correct temperature. With the energy monitoring equipment, I could see the difference in cost between the two settings. Now, I put the ovens on 2 and leave them to get up to temperature – and I’ve saved myself at least £100 a year.”