Enough is enough: why you shouldn’t put up with poor rectifiers any more

You wouldn’t keep a car which kept breaking down, so why do so many tower owners battle on with sub-par rectifiers?

Read this article to learn:

  • Why rectifiers aren’t performing in developing markets
  • How the industry has been coping with poor rectifier performance to date
  • What solutions can make a difference
  • How a sealed system can deliver results for off grid and poor grid sites

In an industry where towercos are spending as much as 60% of their opex on fuel consumption, capex-heavy investments such as deploying solar power or switching from lead acid to lithium batteries can help them to make gains and improve margins as they decrease their reliance on an unpredictable fuel supply chain. However, as much as towercos might spend on their power systems, they have still had to put up with unreliable rectifiers which have struggled to cope with the dust, heat and humidity at many locations. According to Mattias Karlsson, Vice President eSite at Flexenclosure, as many as 20% of rectifiers can fail each year in off grid and poor grid locations across Africa, Asia and the Middle East, adding costs through downtime, replacements and man hours across the maintenance cycle.

Why do rectifiers perform so poorly in developing markets?

Towercos, particularly those in emerging markets, are under two competing pressures: the need to offer a reliable service to their tenants – to meet SLAs and to create resilient and robust networks – and the downward pressure on pricing driven by huge leaps in data consumption with static or declining ARPUs. This pressure to deliver uninterrupted uptime while at the same time needing to drive down opex, is forcing towercos to re-evaluate their operations and maximise performance.

The environment at sites in much of Africa and parts of Asia and Latin America is tough: they are typically hot and dusty, often with high humidity. To make matters more difficult still, the electrical environment – both from poor grid supply and from diesel generators – is very inconsistent, with ageing gensets often producing damaging voltage spikes.

To date, most of the rectifiers in the market have been designed for indoor, on-grid use in developed markets like Europe or the USA and have been designed under the assumption that they would be working with a high quality and consistent power supply – something which simply doesn’t exist in most developing nations. They’re also often being repaired or maintained by field teams who lack the appropriate specialist training. If towercos can’t rely on rectifiers to get uninterrupted DC power it has an immediate effect on uptime, meaning their bottom line is hit by both the cost of replacement or repair and penalties imposed by their tenants as part of their SLAs. Even if a failure doesn’t lead to downtime, it will result in higher operational costs as batteries and generators won’t be performing optimally, creating a lot of pain for the site owner.

Mattias Karlsson thinks the problem comes from how telecoms infrastructure has evolved. ‘Telecoms first rolled out in Europe and the US in nice and reliable on-grid areas, and that’s what the technology was developed for. When wireless communications rolled out in less developed countries, the suppliers in those markets tried to create the illusion of a safe indoor setting by putting low cost indoor rectifiers inside a cabinet.  The fact is though that even protected by a cabinet, these rectifiers simply aren’t robust enough for the more extreme operating environments that their cabinets were put in. But with no alternative available, towercos had no option but to accept the situation and try to push away the pain of dealing with rectifier failures to their suppliers.’

Why hasn’t a solution been found before?

Rectifiers are delicate bits of kit in terms of power generation, more prone to falling foul of the local climate than batteries or gensets. With cabinetry offering limited protection, the scope of solutions to address the problem was also limited so nothing much changed.

In addition, the problem was perpetuated by the way that RFPs and many procurement functions were set up. With no accepted alternative in place, RFPs based around traditional power systems requested the same elements and configurations that had always been used and didn’t leave much room for innovation in terms of the whole power system. And introducing something completely new would take time to find acceptance in slow moving supply chains.

The result was that towercos had no alternative but to accept poor rectifier performance as the status quo. With the available solutions having been created for other environments, expectations were low in terms of how fit for purpose they could be. However, Flexenclosure has been working to change this. ‘No one really looked at sub-Saharan Africa with a view to designing and building solutions specifically for that market,’ says Karlsson. ‘So that’s exactly what we’ve done. We solved a problem that towercos in developing nations face every day, with a solution specifically designed for them and the very difficult environments in which they operate.’

What’s the solution?

Thanks to Flexenclosure’s extensive experience working in off-grid and poor grid areas, there is now a much better solution for this. They redesigned every component from the ground up – specifically to withstand the harshest possible conditions – and then encased the electronics in a totally sealed box, thus creating a true outdoor product which will never be exposed to dust or humidity and is completely tamper-proof. Their eSite x10 site power solution is designed to address fluctuations in voltage, varying environmental conditions on site and is purpose built for the market.

‘People have tested so many brands and types of rectifier and they all fail in the same way, so why should they trust us?’ challenges Karlsson. ‘They need to see how radically different our solution is. If we think back to the days of rotary dial telephones, if someone had come along then and said ‘you don’t need that any more, here’s an iPhone’ we would never have believed it. But that’s what we’re doing with our eSite x10 as it’s so fundamentally different to how site power has been done in the past. We’ve completely overcome the technology issues.  The challenge now is to help towercos in developing nations understand that they really don’t have to put up with second-best anymore.’

Where is it working?

‘In the three years since we launched eSite x10 and started to deploy it across Africa, the Middle East and Asia, we’ve had zero failed rectifiers. It is deployed in around 20 countries now and we’ve had no failures in that entire time,’ stated Karlsson.

Operationally, around 20% of rectifiers in off-grid and poor grid locations are replaced every year, so Flexenclosure’s initial findings support their belief that the eSite x10 solution could completely change the game in terms of rectifier performance.

But that’s not all – when Flexenclosure works with a towerco, their eSite x10 systems connect to a server and their built-in eSite Tools RMS collects data which can support customers in optimising their power performance at a site level. Flexenclosure has found ESCOs in particular have understood the benefits of the eSite Tools offering as they seek to further optimise their operational spend.

‘We worked with an ESCO in Burkina Faso, across different sites with batteries or solar depending on grid availability, and then used our eSite Tools RMS data to optimise the settings not for the network as a whole but for each and every individual site. This ability to monitor and fine-tune performance at a site level will make a big difference, not just to fuel consumption or maximising battery life, but to an ESCO’s overall profitability,’ added Karlsson.

Site data: an added benefit

While the eSite x10 is maintenance free, with no filters or fans to maintain, it can also drive down maintenance needs for the rest of the site by improving operational performance. One major benefit of such a robust rectifier is that it can significantly improve the efficiency of a site. ‘In a standard system, the rectifier can only harvest power from the grid when the supply is good, whereas eSite x10 can safely and effectively harvest any available power regardless of how bad the grid is. This can mean that at some sites a genset isn’t needed at all,’ says Karlsson.

Flexenclosure has patented its own inbuilt ATS, which protects the system and makes intelligent decisions about when to switch between grid and genset power. It can also log all grid parameters so it’s possible to track exactly how the grid is behaving. This is a powerful tool for towercos or operators when they’re negotiating with their grid power supplier, as they can show what they’re actually receiving versus what they are paying for.

‘Customers want reliable site data,’ says Karlsson. ‘We can show in real time how the grid is performing and the data we collect can help site owners make important decisions for investment in battery capacity. eSite Tools not only measures ROI on our x10 system, but on the peripheral equipment they already have, meaning we can offer solid data analysis which will help overall site planning decisions. We see towercos asking for this kind of information, and the transformative power of our optimised data and reports where it’s implemented.’

As with all cutting-edge technology, Flexenclosure anticipates it will take some time for this solution to change the mindsets of towercos and operators who have been working in the same way over the last two decades. But with the evidence speaking for itself, there’s no doubt that the eSite x10 will change the game in terms of improving the reliability and efficiency of tower power across off-grid and poor grid locations worldwide.

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