Rectifiers, converters, inverters, chargers and controllers are often critical to the efficient operation and integration of multiple energy sources at unreliable grid and off-grid cell sites. One of the pioneers in this field is New Zealand developer and manufacturer Enatel, who you’ll find exhibiting at the TowerXchange Meetup Africa & Middle East this October. We caught up with Damien O’Regan to find out more about Enatel’s capabilities.
TowerXchange: Where do Enatel fit in the telecoms infrastructure supply chain?
Damien O’Regan, Global Sales Manager, Enatel Energy:
We are a New Zealand-based energy equipment manufacturer. Enatel Energy designs and manufactures a range of rectifiers, converters, inverters, solar and wind chargers across multiple voltages for telecoms and industrial applications.
Enatel is made up of three divisions. Enasolar manufacture a range of grid-tied solar inverters whilst the Motive Power group supply a suite of modular, high efficiency fast chargers. These are able to automatically identify the types of battery connected over the powerline and apply the necessary voltage and charge profile. A long association with leading battery manufacturers has been a crucial contributor in identifying industry challenges and driving charger innovation.
TowerXchange: What are your channels to market?
Damien O’Regan, Global Sales Manager, Enatel Energy:
We are headquartered in Christchurch, New Zealand, with direct representation via an operation in Croatia who manage parts of Europe; with Enatel Shenzhen responsible for the domestic Chinese market. However our primary business model is one that identifies and supports highly capable local partners. The results and potential is evident, for example in one instance I worked with a distributer that grew from 3 to 200 staff, driven primarily by the demand for DC power systems.
Strong relationships are crucial in tailoring systems to meet specific requirements within local environments - Enatel supplies power modules and system building blocks for integration. Alternatively, turnkey indoor and outdoor solutions are available. Our designers and decision makers are only ever one call away - we maintain very high levels of engagement, support and training.
TowerXchange: What is the ‘sweet spot’ for Enatel’s solutions - on-grid, unreliable grid, off-grid? What’s the typical load?
Damien O’Regan, Global Sales Manager, Enatel Energy:
Our typical applications have historically been grid connected standby power solutions where operators demand the highest levels of uptime. Demand and growth in emerging markets meant less grid dependence. Providing energy solutions for off-grid sites is a more recent challenge and one that allows us to apply innovative solutions to produce demonstrable and desired benefits
Our portfolio can support any load requirements from a 100W to 100s of kW’s, but in a hybrid context we most frequently find ourselves supporting 1-3kW loads. Whilst it’s possible to go outside this, careful dimensioning and evaluation of economics is necessary.
TowerXchange: Has backup power become a commoditised market?
Damien O’Regan, Global Sales Manager, Enatel Energy:
Within telco networks it’s a fair conclusion based on volumes supplied, system generalisations and dollar per Watt erosions over past decades. However, sufficient and sometimes significant differentiation can still remain, particularly with the emergence of niche applications and recognition of particular capabilities. Commodification risks ‘me-too’ products that fail to suitably meet industry principles and foundations. Systems may aesthetically and technically appear similar, but that’s largely a consequence of industry drivers. Clear distinctions normally exist at nuts, bolts and deliverables level. We’ve refused to compromise - the bottom line is we must be able to support and maintain high 9s availability.
Tower companies target uptimes between 2 to 4 nines (99% to 99.99%) which represent site downtimes of three days to one hour per year. For partial grid and off-grid sites, delivering higher nines goes beyond rectifier MTBF’s and design architectures. It must in combination also include capabilities that address application specific issues, for example, a dependency in diesel generator uptime, information insight and self-healing elements. The towerco model is attractive because of the focus on operators, where delivering QoS means that maximising site uptime is a natural caveat.
Logically, commoditised system limitations can struggle to meet OPEX drivers where the challenges can be far more broad and complicated. Enatel responded to commoditisation by diversifying with an increased focus on partial grid and off-grid applications, viewing network expansion and ruralification in emerging markets as an opportunity to directly leverage our core DNA.
Blending and optimising multiple energy inputs requires the right product portfolio and expertise, but this in association with our specific development efforts has yielded unique capabilities.
TowerXchange: How do you integrate renewable energy and CDC batteries without placing excessive wear on the diesel generator?
Damien O’Regan, Global Sales Manager, Enatel Energy:
The vast majority of all off-grid BTS outages relate to generator issues. Almost total site dependence can rest solely on a generator. For CDC hybrids, fast recharge requirements can overload and stall generators. The DC power community addresses this by limiting battery recharge parameters, sequentially starting rectifiers and delaying aircon startups to avoid excessive inrush currents. The relationship between the generator and cyclic batteries is critical - it necessitates tight but adaptive management. Each element is in continuous change within an environment that also never remains constant.
For CDC hybrids, fast recharge requirements can overload and stall generators. The DC power community addresses this by limiting battery recharge parameters, sequentially starting rectifiers and delaying aircon startups to avoid excessive inrush currents
Increased emphasis must be placed on power conversion devices, particularly as their performance and management capabilities are instrumental in significantly extending lifetimes. Our SYNERGi solution automates and optimises energy generation. During installation, one needs to simply enter the generator nameplate kVA, push the start button to commence the commissioning charge - no further human intervention required to revisit and retune. It automatically caters for variables which may be due to tenants, altitude, wear, weather and diesel quality. It will regularly determine what parameters are required for optimum energy output and automatically adjust to maximise them.
TowerXchange: Is there still a place in the long term planning of cell site energy for diesel generators at off-grid cell sites?
Damien O’Regan, Global Sales Manager, Enatel Energy:
Constant speed AC diesel generators have a bad reputation. Not totally without justification given obvious environmental and economic impacts, but it’s been unfairly compounded, particularly by 24/7 operation. There are already well proven and significant improvements available. Fundamentally this is still about efficiently moving and storing energy. We know a single litre of diesel can be converted into approximately 3 kWh of energy and a review of break specific fuel consumption data is a quick way of digesting generator actualities. Our objective was to develop a solution that was generator agnostic and addresses real-world challenges.
While tower operators should always be looking to reduce their dependence on diesel, present day realities mean diesel generators will be with us for a while. With a reduction in loads and other influencing factors, alternative generation and storage mediums will increasingly come in to play.
TowerXchange: Tower operators always want to know that suppliers are proven in emerging market contexts - what is your installed base in emerging markets?
Damien O’Regan, Global Sales Manager, Enatel Energy:
We have many hundreds of thousands of products installed, with the majority in emerging markets. Our power modules have very high levels of protection beyond those you’d typically find.
Enatel was established in 2002 by the same team that founded Swichtec Power Systems, which was pioneering high frequency switch-mode power in telecoms during the mid-80’s. Swichtec grew rapidly and was supplying to the major Chinese operators in 1990s. We opened a large wholly owned facility there in ‘96. Swichtec’s products were recognised as being innovative, robust and there’s good reason you still see them operating in many networks 20 years later. Swichtec became the DC business within Eaton Corporation.
The original Swichtec management team and founding head engineer Dennis Chapman, started Enatel. All remain intimately involved.
Our initial hybrid systems were limited to mining and military contexts. Recent demand has increased and as a consequence, we are engaged in discussions regarding more significant projects.
TowerXchange: Talk to us about how the challenge of hybrid dimensioning to meet the unique requirements of each site can be married up with the economic consideration where less customisation usually means less cost.
Damien O’Regan, Global Sales Manager, Enatel Energy:
The application of hybrid power is complicated, primarily due to the extensive variations within a site and across multiple sites. This has limited the wide deployment of ‘silver bullet’ solutions.
We see many sites dimensioned on the safe side to fit within particular capabilities. Such systems then risk being more about compromise, than optimise
Inherent site variability means a hybrid conversion that works at one site, won’t necessarily work at all or as well on another. This can limit their successful deployment with time and cost complications. We see many sites dimensioned on the safe side to fit within particular capabilities. Such systems then risk being more about compromise, than optimise.
For us, addressing this variability was the catalyst in developing a unique dynamic solution which allows the expediting of multiple site deployments.
The integration of renewable energy generally relies on a site survey or a very clear brief. Often we’re contacted by people saying we want SYNERGi. The modularity of building blocks takes much of the customisation pain off the table. However, there are some basic site information prerequisites which make dimensioning job easier.
TowerXchange: What specific parameters do you need?
Damien O’Regan, Global Sales Manager, Enatel Energy:
Average site load is most critical parameter and almost always assumed to be greater than actual. We look to utilise the existing generator if possible for cost effectiveness and significant operational potential.
We also need:
Generator - size (kVA &/or kW rating). Is it generator only? 1 or 2 generators?
Battery preferences (if any)?
Are there site noise curfew requirements?
Air conditioning/cooling requirements (if any)?</li%
