“You can’t control what you can’t measure.” — Tom DeMarco, a teacher, speaker and author of software engineering topics. The exact same principle applies to energy consumption or energy usage. Energy is a costly resource, and it should be managed effectively just like any other resource in business, right?
Up to now, most businesses haven’t really measured and analysed how their energy is used. Once a month, accounting receives the utility bill and pays the invoice, and that’s pretty much it.
With the advent of smart metering technology and Big Data, we can now look under the hood of the business and better understand our energy usage. Where is it all going and when?
A whole wealth of useful information can come out of performing an analysis of your business’s energy usage. Not only will this lead to cost savings in the short term, but also assist in designing the optimally sized solar PV plant.
Used correctly, the data can even assist you in spotting operational improvements that impact energy usage and forecast future energy usage!
Smart meters are also able to give your business a baseline model.
- A baseline model is a theoretical measurement of a company’s maximum and minimum demand over a certain period of time. Energy demand data is normally collected over a period of 12 to 36 months, or a full business cycle. This data is used for calculating and verifying energy savings on energy efficiency projects and also used for designing an optimally sized PV system.
Spoiler ahead, it’s time to dive a bit deeper into understanding your facility’s energy demand a bit better!
Reading your utility bill at the end of each month is kind of counterproductive and doesn’t really add much value in terms of understanding where your energy is being used and when it’s being used.
What’s needed is a way to collect and display the data in real-time through a graphic interface.
The smart meter like eGgauge is just that solution.
There are countless different types of smart meters out there, but at their core, they all perform the basic function of collecting energy usage and displaying it through a graphical interface.
Smart meters can be connected to either your main supply to quantify the facility’s total energy consumption or even individual Significant Energy Users.
What’s interesting to point out is that each type of business has a different demand profile. The energy demand profile of a hotel, for instance, would be completely different than that of a cold storage facility.
The graph below shows the energy demand profile of a typical weekday for a 5-star hotel.
The information in this graph shows you when the hotel opens for business in the morning and kitchen staff start preparing food, along with hotel guests taking showers. This places an extra load on the hotel’s boilers. The HVAC system also operates a lot harder with an increase of hotel staff and guests, and with the building warming up during the daytime. The demand then tapers off during the course of the day until off-peak hours.
Now the energy demand profile shows the profile of a cold storage facility for a fruit packing warehouse. The facility has quite a high baseload. A baseload is a measure of a facility’s permanent minimum load over the baseline period.
Data like this assists in optimising energy usage and reducing monthly demand charges. Many companies are charged demand charges on top of an energy consumption charge—the amount of money you pay each month for the number of kWhs used. A demand charge is a charge based on the maximum demand the facilities uses over a period of 30 minutes in a 30 day period.
To explain it in layman's terms though: Each electrical device has a wattage rating, so if all electrical devices were switched on at the same time at a facility for half an hour for that month, then you would be billed for that maximum demand.
A smart meter would be able to identify that before the end of month, so costly demand charges can be avoided. In fact, many smart meters have alarms that can be set up to warn you that the facility is approaching its maximum demand so action can be taken.
This data will also assist in ensuring that when electrical devices are switched on, they aren't all switched on at once but rather staged over a period of time.
Having an idea of the facility’s demand profile will also assist in optimising energy usage if your business is on a TOU tariff. Having access to hourly data, one can shift non-essential loads to off-peak hours when electricity is cheaper. This concept in the sustainable energy space is known as Load Shifting. The data can also be used to make sure that only core operational processes that are absolutely necessary run during peak hours when electricity is more expensive.
- Load Shifting is a sustainable energy concept of optimising energy usage by moving non-essential loads to off-peak hours when electricity is cheaper due to TOU tariff. The strategy involves the knowledge of the facility’s demand profile. The data can also be used to make sure that only core operational processes that are absolutely necessary run during peak hours when electricity is more expensive.
How does having an insight into your facility’s energy demand assist in designing a solar PV system?
Well, sizing a solar PV system is a very fine balancing act and in today’s world data is king!
Having access to hourly data for a full business cycle of 12 months will identify the periods of maximum and minimum demand and how frequently they occur during the day and year. Are the peak energy demands during the day or night?
One of the reasons why solar PV is an ideal solution for reducing a facility’s energy costs is that more often than not the peak demand is during the day.
Ideally, one wants to match the demand curve with the solar yield curve as close as possible to fully benefit from reducing the peak demand consumed from the grid.
A good example here is the demand profile for an office facility.
The energy demand profile for an office facility has a bell-shaped curve.
The weekday profile picks up early morning when the business day starts, and people start arriving at work and switching lights, office equipment and HVAC systems on. It then tapers off at the end of the work day. The weekend demand profile shows the base load for the building.
Now a solar PV yield profile closely matches the demand profile of an office.
When sizing the solar PV system, though, one wants to ensure the daily peak yield is as close to the peak demand as possible during the same time period, roughly midday in this instance.
Cold storage facilities are also excellent candidates for cold storage facilities as they tend to have high base loads. A solar PV system will assist in reducing the high base load of a cold storage facility.
If your business is on a TOU tariff, where the peak tariff rate is during the daytime, then your business facility will further benefit from solar PV as it will significantly increase self-reliance during the day and therefore reduce grid energy consumption.
Understanding your business’s energy demand profile is an imperative part of understanding and controlling your energy usage. As a resource, energy is costly and in many companies it forms a major part of input costs. A lot of energy goes to waste, though, as no process is put in place to track and analyse energy consumption. The majority of businesses don’t know where their energy is going and how it’s being used.
With the advent of smart metering, energy demand data is collected and displayed graphically in real time. This data can be used to pick up anomalies and track trends over time. This data is also useful in determining energy savings for energy efficiency improvements.
Energy demand data goes hand in hand with optimising energy efficiency and Solar PV energy production. As the age-old expression goes, “You can’t have one without the other.”
The data can also be used to design an optimally sized solar PV system. Having a solar PV system that is sized correctly will ensure your level of energy production is maximised according to the facility’s energy demand.
If you want to see how much solar or battery storage could save you over the next 5 years, then take our solar saving calculator quiz below!
Or talk to an Instyle Solar expert about the best solutions for home energy storage or PV-panels.
Otherwise, head back to the solar blog to find even more great educational content.
Photo credit: Depositphotos, Damon Lapping, ResearchGate