ON SEPTEMBER 1, around six a.m., we had a reminder that we are still vulnerable to power outages in spite of having one of the best and most reliable power companies in the region. The thing is, I didn’t know there was an outage until I started seeing WhatsApp messages. My home operates on a battery-based grid interactive solar powered system, which most people call an off-grid system. The vast majority of Barbadians who have invested in a solar powered system have a grid-tied system and all of them would have been without power.
Several businesses were out of power for more than six hours and some even closed for the day. The outage was too long for most uninterruptible power supplies (UPSs), so system administrators where very busy trying to shut down systems before the UPS lost power too. There were also some companies that had generator failure, which is not surprising because many companies install them and never routinely test them or maintain them. The only people who were not affected were those with functioning generators, people with off-grid systems, and people with battery backup systems.
Although outages are not common, I am sure this one caused several IT system administrators, business owners and homeowners to start reviewing their backup power situation. Generator sales will probably go up, but in the age of renewable energy, I am urging people to consider a more sustainable alternative. Battery-based systems are yet to be widespread as an alternative to a grid-tied system for homes and businesses, but this event should cause some people to think differently. If you are investing a significant amount of money in a renewable energy system and you have any need for sustaining your power why are you not considering a battery-based system?
IT system administrators are still living in the world of generators and UPS. The only consideration is what size UPS and/or what size generator the business should buy. They should implement a renewable energy system that will cut operating costs and provide indefinite backup. Small companies’ strategy is normally a single stage backup using a UPS and the medium size to larger companies use a two-stage backup with a UPS and a generator.
Stage one: The UPS is the first line of defence. It is solid state with no moving parts and therefore it’s meant to respond immediately to a power loss. The UPS is a special purpose system with some of the fundamental components of a battery-based system. It has an inverter and it has batteries much like a battery based system. What’s specialised about it is that it communicates with the servers to shut them down when they are out of backup power and they provide line conditioning for the servers. In an effort to package these UPS in one small as possible “black box” the manufacturers use small nickel cadmium or maintenance-free lead acid batteries which mean there is limited storage. They look good and compact, but are not practical therefore they provide limited backup for the IT systems. This typically means there is only 30 minutes to an hour backup time; more is very expensive.
Stage two: The generator is a mechanical device and takes time to get started and up to operating speed, therefore, this normally comes on stream after the UPS. There are many things to consider with a generator. The first challenge is the voltage and frequency stability. IT equipment is very sensitive and therefore line conditioning is critical when using a generator. This is normally provided by the UPS.
However, depending on how much money you spend the performance will vary and this could be a problem. Secondly, generators are not meant to run constantly as it is a mechanical device, but power outages are not normally more than two to four hours. If there is a natural disaster, and prolonged periods of operation is required, this can become a serious challenge. Lastly, a generator requires weekly to bi-weekly start ups and running for at least 15 minutes to make sure it is functioning properly and to allow the moving parts to be lubricated. A generator is based on a diesel engine and therefore needs to be serviced and the components checked to ensure they are ok.
The alternative is a solid state system that is constantly providing power to your systems from clean renewable energy. The system will always be isolated from the utility power and therefore is not subjected to power instabilities created by the inductive powered devices in your building like the air conditioning units. Secondly, your IT systems will always be operating isolated from the utility power therefore there is no need to be concerned about a power outage.
The reliability of the technology is the same that IT administrators has been relying on for years. It has the same components as a UPS with solar panels added, which has no moving parts with a 25-year warranty and the utility would now become your backup or a generator if you want.
Battery options are vast, with many options for batteries which is dependent on budget and operational requirements. The comparative cost of a renewable energy system to a UPS and generator varies, but typically, the renewable energy system will cost more. However, the renewable energy system will save you operating cost because it will not be using utility power, so when the analysis is done the difference in cost is mitigated by the yearly operational savings. The power outage should be a wake-up for business and IT administrators that the solution which has been used for years is not perfect.
Jerry Franklin is managing director of EnSmart Inc. Franklin is an engineer, energy auditor, equipment tester, and energy solutions provider. He is also vice-president of the Barbados Renewable Energy Association. Email: [email protected]
