Carbon Neutral Power Solution for Off-Grid and Poor-Grid Telecom Sites

November 26, 2019 by Paul Shepard

According to the GSMA there are more than one million off-grid / poor-grid telecoms sites in use globally, which combined are generating a carbon footprint greater than countries such as Nepal, Cambodia and Cameroon. By leveraging the environmental benefits of biofuels and supporting ethically approved CO2 offsetting processes such as tree planting or renewable energy sources, such as photovoltaic electricity, for remote communities, Controllis Zero is poised to help large Telco's meet their legal, shareholder and green obligations.

Controllis, a leading supplier of hybrid power systems for mobile network operators (MNOs) and tower companies, has leveraged its experience to develop a carbon neutral site power system to help support a net zero emissions economy, established by the Paris Agreement.

Controllis Zero will allow off-grid and poor-grid sites to produce cleaner energy overall by replacing their dependency on fossil fuels with an eco-friendly solar and biofuel alternative.

Based on Controllis' proven and globally deployed Modular48 dc power system, (which already reduces carbon emissions by up to 90 percent by harnessing solar power and rechargeable lithium ion batteries), Controllis Zero will allow MNOs and tower companies to overcome the final 10 percent of the CO2 emissions challenge.

Controllis Zero carbon telecom power solution (click on image to enlarge)

Controllis has been able to achieve this carbon-neutral status by considering the carbon cycle process in its entirety and adapting its unique dc generator technology to run on E100 bioethanol instead of diesel. All this is accomplished without compromising network uptime.

"With global warming increasing and net zero targets looming, companies are under increasing pressure to operate in a more sustainable way", explains Simon Albury, Managing Director of Controllis. "Controllis Zero has been developed with efficiency initiatives such as OFGEM's ECO in mind and any CO2 released during energy production is offset by a carbon-neutral biofuel manufacturing process."

The Controllis Zero biofuel lifecycle:

  • The manufacture of E100 bioethanol during the plant growth stage is carbon negative because CO2 is converted into oxygen by photosynthesis
  • CO2 emissions during bioethanol fermentation and distillation are counterbalanced by ethical offset programs supported by the United Nations
  • E100 bioethanol is shipped to different locations using the greenest modes of land and sea transport. The emissions for the transport phase are also offset.
  • Controllis' hybrid solar lithium ion solution is the principal power source up to 90% of the time. The remaining 10% is produced by Controllis' bioethanol-powered generator

Cost-Effective & Scalable Lithium-Iron Phosphate Battery Pack

The Controllis IonLiFe® 48-105 is a 105 Amp hour 48V lithium-iron phosphate battery pack designed specifically for telecommunications deployment. The IonLiFe 48-105 fits into a standard 19” ETSI rack and multiple units can be clustered to create a substantial battery bank. The lithium-ion cost per kilowatt hour cycle is now lower than that of lead-acid thanks to its much higher cycle life – making it well-suited for hybrid applications.

Controllis has deployed many hybrid systems using both lead-acid and lithium-ion batteries. The company has now standardized on using lithium-ion phosphate because it is more cost effective over the whole life of the battery system and provides important technical, operational and logistical advantages. These include:

  • Superior usable capacity
  • Extended cycle life
  • Fast charging and less ‘wasted’ energy when charging
  • Ability to deliver full capacity at high current
  • Lower maintenance requirements
  • Easier storage and deployment
  • Smaller and lighter than lead-acid
  • More cost effective than lead-acid

Intelligent Control

Controllis IonLiFe batteries communicate directly with the Controllis RSC-HMU hybrid system controller which also regulates the charge current and voltage supplied to the batteries from the Controllis dc generators. The tight monitoring and control between the batteries and dc generator ensures a long life even in hybrid cyclic charging mode. The IonLiFe® 48-105 is also well-suited for use with renewable solar and wind systems.

Controllis Zero also comprises powerful and secure remote monitoring and analytical tools, giving onsite and offsite maintenance teams meaningful and actionable insights into all aspects of the system's power output and performance levels in real time.

Controllis Zero will be commercially available from Q1 2020.