Save power, save the planet

Blame it on the weather, or credit it to Al Gore's traveling slide show and subsequent Nobel Peace Prize in 2007, but either way the telecoms sector - like many other industries - has developed an eco-conscience. With the news increasingly dominated by stories about climate change and efforts by various governments and organizations to reduce carbon footprints, going green is fast becoming a valuable marketing tool for telecoms/IT vendors and operators alike, whether by putting an emphasis on recycling, sustainable energy and reducing carbon output, or helping their customers to do the same.

Which isn't to say that the telecoms industry has been thumbing its nose at environmental issues up to now. Various companies have been developing ways to run cleaner telecoms networks at least several years before An Inconvenient Truth entered the public eye. But in recent months it's the industry organizations that have been stepping up to the plate. In June, the US-based Telecommunications Industry Association (TIA) announced a series of green initiatives such as databases to help telecoms companies comply with environmental regulations worldwide and recycle old equipment.

One month later, the International Telecommunication Union set up a new group to develop standards related to the impact of information and communication technologies (ICT) on climate change, with a focus on reducing ICT emissions and looking at ways the same technology can be harnessed to help other industry sectors such as energy, transportation and buildings do likewise. The ITU says that ICT could help 'cut global emissions by between 15 to 40%', although this depends on the methodology used to calculate these estimates (which is why a key objective of the group will be to develop internationally agreed methodologies to calculate ICT's effectiveness in emission reduction).

The wireless sector in particular has arguably taken a lead in the quest for green technology. Since at least 2006, the GSM Association has spent a lot of money and time working with vendors and operators to develop base stations running on alternate energy sources such as wind turbines, solar panels and biofuels.

But the main activity for green technology in the wireless sector has been in the area of reducing power consumption, a key contributor to reducing one's carbon footprint. According to ABI Research, infrastructure vendors have been leveraging techniques such as hardware integration, the use of remote radio heads, and software-based solutions that provide dynamic network dimensioning to cut power consumption in base stations. Those efforts alone could reduce average base station power consumption by 43% by 2013, ABI reckons.

Ironically, the push for power efficiency in wireless networks isn't being driven by environmental concerns, but by economics. For many operators, the single biggest chunk of their opex comes from their base station electric bills, and with ARPUs for voice and SMS starting to decline - to say nothing of the rising cost of energy - wireless operators are under pressure to cut costs where they can, says ABI Research vice president Stuart Carlaw.

'Although reducing power consumption provides good ecological credentials for carriers and vendors alike, the real driver for improving power consumption is financial,' he says. 'It is imperative that carriers do everything possible to negate rising energy costs in an environment where network traffic and ARPUs are diverging.'

Emerging markets lead

This is especially the case in emerging markets, where cellcos have already learned to turn a profit on low ARPUs, but face the same market pressures under which ARPUs are hard enough to raise even when you're not trying to offset rising opex costs,


'In India, ARPUs are already at $4 to $5, but the average cost per user is going up, not down,' says Manoj Upadhyay, managing director of India-based Acme Tele Power, which specializes in energy management solutions for cellcos in emerging markets. 'So operators need to cut costs wherever they can.'

Interestingly, however, it's also the emerging markets where some of the most innovative green technology is being developed. The reason: cellcos in such markets face unique power management problems, as they often have to deploy base stations in areas where grid power is intermittent, unreliable or non-existent. Such sites run on a mix of grid power, diesel generators or battery backups.

Consequently, vendors are addressing these problems by looking at new ways to design the tower sites themselves for even further power savings, says Allan Yang, Product Manager, Wireless Solutions, Ericsson (China) Communications.

'Most sustainable energy solutions are driven by the emerging markets that need to provide communication in off-grid area or need efficient and stable power supply,' he says.

The beauty of this, he adds, is that the same techniques that allow tower sites to run without relying on the local power grid can also be applied to any network.

'These solutions can be used in developed markets as well to save the power consumption, and protect the environment by reducing carbon emissions,' Yang says.

Build a better BTS

So how does one design a more eco-friendly base station‾

Some techniques are strikingly simple. For example, base stations that rely on software upgrades to evolve reduced the need to constantly swap out hardware that would then have to be dumped somewhere.

Hardware integration is another technique. Frederic Wauquiez, who looks after mobile networks eco-sustainability at Alcatel-Lucent, says that a module with two integrated transceivers (TRXs) 'can double capacity with the same footprint and reduce power consumption by 32%.'

Advances in power amplifier technology are also helping. For example, one emerging technology - MCPA (multi-carrier power amplifier) technology - amplifies downlink multiple carriers of a base station at the same time, which means base stations can improve coverage and capacity using less power. Wauquiez says the same twin TRX module running on MCPA technology could use up to 60% less power compared to current PA technology.

Vendors have also taken power efficiency to the software level with dynamic power saving techniques based on traffic loads, Wauquiez adds.

The device side also has a role to play by using RF chips that demand less power from the network, says Lonnie McAlister, Intel Connectivity Product Manager, Asia Pacific, for the Embedded Sales Group at Intel.

'Reducing overall power consumption on the board is a key component in any kind of RF design,' McAlister says. 'Also we're trying to fan a much wider spectrum range, from 2.3 to 3. 8 GHz for Wi Fi and Wimax, so we have to work with the industry to design new power amplifiers to meet our service provider requirements for output power.'


Cool sites

Naturally, there's more to reducing power consumption than making the BTS more efficient. The entire BTS site can be designed to accomplish that goal, and even enhance efficiencies, says Ericsson's Yang.

'We're not only concerned with power consumption for the BTS equipment; we also take the complete radio site to the whole radio network into consideration and then optimize the total network energy saving,' he says.

One example, he says, is Ericsson's 'Tower Tube', a BTS tower made on concrete instead of steel, which uses 40% less power than a typical steel tower, much of that from reduced feeder losses and the ability to operate without active cooling.

In fact, air-conditioning is a major focus of site design because it's one of the most power-hungry aspects of the site apart from the actual transmitters, requiring anywhere from 1200 to 2000W to run. A number of vendors have developed base stations that can operate at higher temperatures without the need for A/C, instead using heat exchangers while saving the A/C for backup batteries.

Direct air cooling is another option, in which the cooling is performed using ambient air, a fan and a filter. This set-up takes up less space than a compressor, and also uses less energy.

Companies like Acme Tele have come up with ideas such as a filterless A/C system that doesn't require truck rolls for maintenance and cleaning, and a thermal management system that uses specially engineered phase change materials (PCM), which absorb heat from the equipment, and eliminating the need to use diesel generators to power the A/C.


To be sure, cutting back use of diesel generators is always a good thing, not least because of the current surge in fuel prices. Ericsson says it's been looking at ways to reduce reliance on diesel generators. In Uganda, for instance, where 50% of base stations are powered by diesel, Ericsson has been working with local cellco Celtel to develop a hybrid solution combining generators and a battery bank with specially designed batteries that can handle large amounts of charges and discharges. This allows the towers to alternate between the generators and batteries, cutting diesel usage in half.

That said, wireless vendors would ultimately like to see base stations stop using diesel altogether in favor of alternate energy sources that are self-sustaining and don't require regular refueling. Early interest in biofuels led to a GSMA Development Fund project in India with Ericsson and Idea Cellular, which launched an initiative last year to trial four rural base stations running on biofuel-powered generators (albeit with a mix 80% regular diesel and 20% biofuel). However, earlier this year Idea Cellular CTO Anil Tandan reported that wile the base stations worked fine, they weren't generating significant opex savings.

Part of the problem with biofuel is that there's very little of it being produced, which is due in part to difficulty in finding a sustainable source of biofuel that doesn't also cut into the world's food supply - especially at a time when food prices are already escalating.


The issue has become so controversial that in May, UN food advisor Olivier de Schutter called for a halt on biofuel investment altogether. That said, the Idea/Ericsson trial took a strikingly local approach, using biofuel from Hyderabad made out of used cooking oil from restaurants, but Tandan said that 'there's only a limited supply of biofuel being produced, it's only being produced out of Hyderabad, and there's no distribution system in place for it, so for the moment we're only seeing marginal savings.'

In the meantime, solar and wind power are also viable alternatives, although solar is currently more popular, says ABI Research. However, hybrid solutions including wind and increased use of battery power are becoming more viable. Another GSMA-backed trial in Namibia in 2007 - this time with Motorola and local operator MTC Namibia - demonstrated a hybrid solar/wind powered base station. As Wireless Asia reported in February, the results found that the site generated about 4,500 kg less CO2 a year than one powered on the grid. If the backup diesel generators were removed from the equation, an additional 640 kg of CO2 emissions could be saved.

An additional benefit from this approach has emerged as well: the ability to turn an off-grid base station site into a source of power for local villages as well. According to Motorola, the actual cost of generating power from a hybrid solar/wind station is almost zero, and the excess power can be made available to the local community to support phone recharging or other battery charging requirements without impacting the network operator's equipment.

Acme Tele Power's Upadhyay is even more assertive. 'We can save about 2 kW per tower. Multiply that by 90,000 towers in India and 8600 hours a year, and you'd have enough energy to power Singapore for a few days,' he says.

Heavy opex

Perhaps, but the downside to the green tech story is that, overall, it's still the exception to the rule. Part of that is simply due to the fact that power efficiency has only recently become a chief priority for cellcos, says Wauquiez of Alcatel-Lucent, which he says has been designing its base station gear for better power efficiency for years.

'We would tell this to our customers, but they were more interested in peak performance and capacity,' he says, although he adds that this has changed dramatically in recent times. 'The RFQs used to have just a few questions on power consumption, but now it's pages of them. For example, when we won a contract with Reliance Communications in India last year, power consumption was a key topic. They had ten pages of documents emphasizing the benchmarks they want to see for reducing power.'

The bad news is that, at least for the short term, those power savings won't be enough to offset the growing cost of bulk diesel fuel, coupled with wholesale electricity price increases, says ABI's Carlaw.

'This will result in a collective network opex of $22 billion in 2013,' he says, though he notes that the benefits of power consumption and efficiency advancements should start reining in spiraling operating expenditures - by 2012.

How to calculate your carbon footprint

While cellcos may be chasing power efficiency primarily as a way to cut their opex costs, the same efficiencies also translate to a greener wireless network.


One measure of green technology is the amount of CO2 your equipment generates, also known as a carbon footprint. And there is a direct correlation between the amount of CO2 a specific device, appliance or base station generates in and the amount of electricity it consumes.

'It's not a complex calculation,' says Adam Kleemeyer, head of Enterprise Data Product and Solutions Marketing at Nortel Asia. 'Basically if you know how many kilowatts per hour (kWh) your equipment is using, you can multiply the number of kWh by the amount of grams of carbon dioxide produced per kilowatt.'

That said, there is a little more to it than that - for a start, the amount of CO2 per kWh depends on whether the power is being generated by coal, gas, hydro power or solar panels, for example. But once local data is plugged in, the rest is simple math.

The same basic math can also be used to work out things like how much money you can save as your carbon footprint comes down. There are already a number of web sites from green groups like Carbon Footprint and Climate Crisis that calculate carbon footprints for residences and businesses. For something a little closer to the telecoms/IT space, Nortel Networks recently launched its own Web-based Energy Efficiency Calculator.

At the moment it's designed for enterprise networks and data centers, not cellular or wireless broadband networks, and its chief mission is to compare Nortel's COperformance vs Cisco Systems (and Nortel typically wins, although the data has been verified by the Tolly Group).

But the calculator demonstrates how easy it is to work out how much COthe network is generating and how much it's costing you on average, by market.

It can even tell you how much A/C power you need for your gear, says Kleemeyer. 'You can measure the amount of heat dissipated from your products in thermal units, so people can use that to calculate how much A/C they need to balance it out.'

Watch your energy levels

Reducing carbon emissions is everyone's responsibility, and short-range wireless technologies can help consumers do their part by watching how much energy they consume.

'Smart metering' technology that allows public utility companies to use Internet technology to remotely track how much water, gas and electricity you use can also be deployed in 'home area networks' (HANs) that will not only give utilities greater management efficiencies, but also provide customers with choices about their consumption, according to ABI Research senior analyst Sam Lucero.

'We believe that in an era of rising energy costs the HAN model - and its most sophisticated outgrowth, the Energy Management System - will eventually see wide deployment,' Lucero says.

The HAN is an extension of smart metering intelligence into the home itself, connecting the meter to 'load centers': major power-consuming devices such as 'smart thermostats,' air conditioners, and washer/dryers. While a few utilities today manage peak demand by directly capping these load centers' usage, a HAN system would allow the homeowner to specify a mix of consumption and efficiency across a range of devices, ABI says.


Four technologies are jostling for position in this space: ZigBee, Z-Wave (both already used for home automation), 6loWPAN and HomePlug Command and Control (HPCC), which communicates data over the building's electrical wiring.

Lucero says ZigBee is the most likely candidate for HAN success. 'It enjoys wide support from utilities. The ZigBee Alliance has been very focused on smart metering.'

Z-Wave also has support in the home automation market, especially in North America and Europe. 6loWPAN is the dark horse, technically sound but new and relatively untested in the market, while HPCC can only serve wired devices.