In poor or unstable grid scenarios, batteries installed on cell sites are regularly subjected to uncontrolled partial state of charge (PSOC) conditions and medium to high cyclic use. This, coupled with the often high ambient temperatures at such sites, puts significant stress on the energy storage system in place. Enersys’ deep discharge capable batteries have had significant success in other applications and the company is now introducing their PSOC capable Genesis EP battery to the telecom market. TowerXchange speak to Enersys, one of the global leaders of energy storage solutions to learn more.
TowerXchange: Please can you provide an introduction to EnerSys® for those who are not familiar with the company?
Anssi Laitinen, Marketing Director, Reserve Power EMEA, EnerSys:
EnerSys is the global leader in stored energy solutions for industrial applications. We manufacture and distribute reserve power and motive power batteries, battery chargers, power equipment, battery accessories and outdoor equipment enclosure solutions to customers worldwide.
Motive power batteries and chargers are utilised in electric forklift trucks and other commercial electric powered vehicles. Reserve power batteries are used in the telecommunication and utility industries, uninterruptible power supplies, and numerous applications requiring stored energy solutions including medical, aerospace and defence systems. Outdoor equipment enclosure products are utilised in the telecommunication, cable, utility, transportation industries and by government and defence customers. EnerSys also provides aftermarket and customer support services to customers from over 100 countries through our sales and manufacturing locations around the world.
We have extensive long term experience in power management in Middle Eastern and African telecom backup power applications. EnerSys has also introduced many innovative solutions, such as SBS® EON Technology® batteries that provide up to four times more cycles than the standard Absorbent Glass Matt (AGM) batteries in hybrid applications.
TowerXchange: Why is it imperative for tower companies and operators to consider the location of the towers when deciding on their choice of batteries? How does grid availability and reliability affect battery choice?
Anssi Laitinen, Marketing Director, Reserve Power EMEA, EnerSys:
In general, the grid connectivity or lack of it can be divided to three main areas:
In the stable grid environment there is only minimal cyclic use for batteries and a relative stable ambient temperature. The stable grid does not necessarily demand a battery compatible with harsh conditions.
The unreliable grid may need a battery capable of withstanding partial state of charge and to handle more repeating cycles. In the off-grid scenario we typically find a diesel generator and battery as a ‘hybrid’ solution. The hybrid solution can also incorporate renewable energy sources such as a wind turbine or photovoltaic array. Warm ambient temperature and regular cyclic use in the off-grid scenario place again different demands for the battery. Understandably it is challenging to choose the right battery, and in addition one needs to also consider related equipment such as outdoor enclosures. A one fit for all approach does not work in these scenarios.
TowerXchange: Considering that poor-grid is still quite common in most parts of Africa what new solutions are available for sites situated on poor-grid? How extensively have these been deployed?
Anssi Laitinen, Marketing Director, Reserve Power EMEA, EnerSys:
When there is a poor or unstable grid this often means that there is a condition what we call uncontrolled cyclic use of batteries. Very often there is also a warm ambient climate. The battery solutions available should match to the uncontrolled partial state of charge (PSOC) conditions and the medium to high cyclic use of the battery. We have recently introduced a PSOC capable Genesis EP® battery which is based on thin plate pure lead technology and has enhanced the ability to recover from deep discharge. This helps in case the battery has entered to this state of discharge, which is quite common in these grid type conditions. EnerSys has earlier introduced these type of deep discharge capable batteries in other applications such as renewables and home energy storage, and now we are introducing this to the telecom environment.
We have recently introduced a PSOC capable Genesis EP® battery which is based on thin plate pure lead technology and has enhanced the ability to recover from deep discharge. This helps in case the battery has entered to this state of discharge, which is quite common in these grid type conditions
TowerXchange: In terms of reducing the total cost of ownership of power management there are multiple choices available for equipment such as cabinets, cooling and rectifiers. How does the choice of each affect costs and what recommendations does EnerSys have?
Anssi Laitinen, Marketing Director, Reserve Power EMEA, EnerSys:
This is a question that may need a webinar or a lecture to answer in detail, but I will try to provide a short answer here.
In general, the Capex (Capital Expenditure) costs for batteries consist of the battery costs, transportation, installation and overheads. The Opex (Operating Expenditure) costs then cover energy consumption and maintenance of the backup power solution. We have TCO (Total Cost of Ownership) calculators in place for discussion with our customers to assist them with their choices.
However, in the hybrid scenario, the generator maintenance costs and the fuel savings and site visit costs are important considerations .The battery needs to recharge quickly and withstand the high cyclic use. The EnerSys hybrid calculator provides guidance for even the most complex total cost of ownership questions.
The cabinet TCO calculations are covering the capital and operating expenditures but are also based on the following criteria: need for equipment protection in general, free cooling, air conditioning and need for anti-theft features. The outside temperature places demands for the cabinet and cooling method choices. In comparison with batteries, one deployment strategy rarely fits. You will need to consider the need for cooling batteries and other equipment such as rectifiers and power equipment. Some batteries can withstand higher temperatures so you may not want to have the most expensive cooling method, however, in the hybrid scenario the cycles may kill the battery before the temperature element starts to affect the battery life.
TowerXchange: Battery theft is a major issue at the moment. Are there new ways to combat this?
Anssi Laitinen, Marketing Director, Reserve Power EMEA, EnerSys:
There are two ways to look at battery theft from the site operations perspective. If the strategy is to retrofit existing sites with battery protection, then we have battery protection alternatives. If however you want to start a green field operation and need both new battery cabinets and batteries, our outdoor enclosures can provide anti-theft features today.
There are more than half a dozen different protection features available in our cabinets. Thus if you are considering a new site with new cabinet options then you should look at the anti-theft features available both in the cabinet and in the batteries.
TowerXchange: Should tower companies look at remote monitoring of batteries and what benefits this will bring?
Anssi Laitinen, Marketing Director, Reserve Power EMEA, EnerSys:
Most definitely they should. With remote monitoring, one reduces the need for site visits. Many industries are already using remote monitoring of their equipment. The benefits are key here with the protection of assets. This can be 24/7 and this can be crucial for instance in the hybrid-off grid scenario as in these sites the backup power solutions provide for the real operation of the site, hence the need for better monitoring. There are additional benefits available if one wants to consider even more advanced solutions: remote management. Instead of sending someone on site, the voltage of a battery can now be corrected remotely, saving an unnecessary site visit.
strong>EnerSys will be exhibiting at the 5th Annual TowerXchange Meetup Africa & Middle East, being held on 3-4 October at the Sandton Convention Centre, Johannesburg. Visit the website for more information
