Ensuring your valuable assets, such as food, reagents, enzymes, RNA, DNA, embryos and proteins are properly protected in cold storage is difficult enough under normal circumstances. What if you had to contend with rolling power outages that could last for days or weeks? This is the situation faced by many laboratories, biobanks, food processors and diagnostics organizations in California these days.
As part of an effort to prevent deadly wildfires like the Camp Fire last year that killed 86 people, Pacific Gas and Electric (PGE) has started a program to cut power to large swaths of customers when conditions are right for wildfires. It is believed that the Camp Fire and many other wildfires were sparked by trees brushing up against power lines and equipment. When winds are high and conditions are dry, like they are now, PGE plans to cut power in an attempt to prevent sparking more wildfires. These power outages are expected to last for days in many cases.
Clearly this presents a problem for all of their customers from typical family homes to restaurants to retail outlets, but one of the greatest impacts is to laboratories and researchers storing valuable, and often irreplaceable, items.
The journal Nature recently documented the challenges researchers face trying to protect their assets in cold storage. Facilities without power, like UC Berkeley, are shutting down and telling employees and students to stay home because they can’t conduct business with the power out.
Jessica Lyons, a molecular biologist at UC Berkeley, says that each lab in her building has a single outlet that is connected to an emergency power system. The main freezer in Lyons' lab, which keeps specimens at -80 °C, is plugged into that outlet. Lyons and her colleagues stocked the other freezers in their lab with dry ice on 8 October after being warned of the impending outages, to keep things cool.
“For any scientist, the bottom line is are all of the freezers getting power right now, or are they not,” she says. “I actually don’t know the answer to that right now, and they keep telling us not to come in.”
If you are running a facility with cold storage and you are likely to have to deal with power outages what features should you be looking for in an alerting and monitoring system?
- Battery powered sensors - so they continue to work even when the power doesn’t
- Cellular back-up so data is still uploaded to the Cloud even when the power and WiFi are down
- Battery back-up for data storage (such as the Gateway) so data is not lost in outage
- Remote alarms to alert you to out of spec conditions in your cold storage and to let you know when the power has gone out
Let’s look at each of these individually.
Battery powered sensors
The Element-T Internet of Things temperature sensor from Elemental Machines is powered by 2 AAA lithium batteries giving it approximately 9 months of battery life. Being battery powered it is unaffected by power outages. The Element-T will continue to monitor and transmit readings via Bluetooth every 15 seconds to the Gateway, which is a tablet computer that not only stores the data but also uploads it the Elemental Cloud.
An example of what a power failure looks like is shown in the chart below from a -80C freezer. The sinusoidal pattern at the beginning of the chart shows the small temperature changes in the freezer as a result of typical compressor cycles. This is what a properly functioning freezer should look like. Just after midnight on 7/13 the power fails. This is when the temperature starts to rise. When it hits -65C it triggers a temperature alert. As can be seen here, the Element-T, combined with the Gateway, continue to monitor and store data even when the power to the facility is out.
Cellular and Battery Back-up
Under normal conditions the Element-T sends readings via Bluetooth to the Gateway. These readings are uploaded to the Elemental Cloud every 15 seconds and can be accessed from anywhere you have an Internet connection. But what happens when the power fails? As can be seen from the graph above, power was out for nearly 8 hours, but there was no loss of data as a result. The battery-powered Element-T kept recording freezer temperature and the Gateway kept storing this data while running on battery itself. This is very important for record keeping and to help the customer decide if the contents of the freezer are compromised or are still in good shape. If everything was powered by the facility’s electrical system these crucial data would be missing.
How do you know if your freezer is failing because of a power outage? One way is to wait for the freezer temperature to go out of range and get a temperature alert. Modern -80C freezers can hold temperature pretty well without power so it might take several hours for you to learn you’ve lost power by waiting for a temperature alert.
If you use a Gateway that normally works on wall power, but has a battery back-up, you can set an alarm to tell you when the Gateway has stopped using wall power and is running off battery. Fortunately you can set up such alerts in the Elemental Machines platform.
The image below shows the email alerts sent to the lab director from the power outage we looked at earlier. You can see he was alerted almost immediately to the fact that the Gateway lost power. In this way you can determine if your problem is a facility-wide power outage or just one freezer that is out of range.
In addition to email alerts, the system will also send text message alerts to the appropriate people or groups of people.
We certainly hope that California doesn’t have a wildfire season like they did last year and that forced power outages are a rarity. However unexpected power outages happen all the time throughout the world. It’s best to be prepared for the worst case scenario by using a robust system like the Elemental Machines platform. For your very own demonstration, please contact us.