With next-generation fixed wireless access (ngFWA), operators can build high-performance broadband networks with extended service lifetimes and cost-effective scalability. One aspect of delivering broadband that is not always considered is environmental impact. Carbon footprint can be substantial and may vary significantly depending on the technology employed. As responsible environmental custodians, it is worthwhile to examine these costs in greater detail.
As an example, we’ve found that when calculated on a per-subscriber basis, the Tarana ngFWA G1 platform generates 55% less cumulative carbon emissions compared to a fiber-to-the-home deployment, and 70% less net present carbon emissions. (Download the full white paper for the complete analysis.)
The Carbon Cost of Technology
Carbon footprint is a measurement of the quantity of detrimental greenhouse gasses emitted throughout the entire life cycle of a product or service. The construction of infrastructure entails a tangible expense in terms of carbon footprint, also referred to as carbon dioxide equivalent (CO₂e). Network infrastructure is no different in this respect. What is different, however, is the amount of CO₂e generated by different network technologies.
Fiber CO₂e Emission
When calculating the carbon cost associated with fiber, three primary values are used: the CO₂e emissions required to manufacture a mile of fiber, to trench a mile of fiber, and the emissions generated by the workforce responsible for laying a mile of fiber. These three figures encompass a range of factors, including the production cost of the fiber itself, the fuel and electricity consumption during the trenching process, as well as the power consumption by fiber electronics.
Based on the provided input values (see the white paper for specifics), we can calculate the total carbon footprint for a mile of fiber as follows:
|
CO₂e to Trench a Mile of Fiber |
|
|
Time to trench a mile of fiber |
10.6 days |
|
Diesel to trench a mile of fiber |
2,686.5 gallons |
|
Total CO₂e per mile trenched |
60,445.4 pounds per mile |
The second component of the total cost for fiber deployment is the workforce required for installation:
|
CO₂e to Trench a Mile of Fiber |
|
|
Workers needed to trench |
5 |
|
Daily roundtrip drive to worksite |
20 miles |
|
Total commute per mile of fiber |
1,056 miles |
|
Gasoline consumed per mile of fiber |
41.6 gallons |
|
Total CO₂e per mile for workforce |
804.9 pounds per mile |
Since the manufacturing of a mile of fiber entails approximately 17.1 pounds of CO₂e emissions, we can obtain the total emissions figure by summing this value with the previously calculated numbers:
Total CO₂e per mile of fiber = 17.1 + 60,445.4 + 804.9 pounds = 61,267.4 pounds (30.5 tons) of CO₂e
Based on our input numbers for the total subscribers supported by a fiber deployment, the average carbon emissions generated per subscriber for the electronics are 27.3 pounds (OLT) and 2,149.7 pounds (ONT). Consequently, we can determine the total CO₂e cost per subscriber as follows:
Lifetime CO₂e/subscriber = .25 miles x 61,267.4 pounds + 2,177 pounds = 17,493.8 pounds (8.7 tons) of CO₂e
Alternatively, we can express the net present lifetime CO₂e per subscriber equivalently as 16,685.6 pounds (8.3 tons).
ngFWA CO₂e Emission
In the case of ngFWA, we examine the CO₂e emissions generated during the construction and installation of a tower, the energy consumption of subscriber electronics, and the workforce needed for tower installation.
Based on the input values, we calculate the total carbon footprint for ngFWA as follows:
|
CO₂e to Erect a Tower |
|
|
Time to erect a tower |
10 days |
|
Diesel to erect a tower |
2,544 gallons |
|
Total CO₂e per tower erected |
57,240 pounds per tower |
|
CO₂e of Workforce to Erect a Tower |
|
|
Workers needed to erect tower |
5 |
|
Daily roundtrip drive to worksite |
20 miles |
|
Total commute per tower |
1,000 miles |
|
Gasoline consumed per tower |
39.4 gallons |
|
Total CO₂e per tower for workforce |
672 pounds per tower |
We obtain the total figure for a tower by summing the emissions from erecting and installing the tower:
Total CO₂e per installed tower = 57,240 + 672 pounds = 57,912 pounds (29 tons) of CO₂e
Based on our input numbers for the total subscribers supported by a wireless deployment and the per-subscriber power requirements, we can calculate the average carbon emissions generated per subscriber. This calculation involves adding the CO₂e emissions from the tower per subscriber, the base node operation per subscriber, and the remote node operation emissions:
Lifetime CO₂e/subscriber = 24.1 + 394.1 + 7,524 pounds = 7,942.2 pounds (4 tons) of CO₂e
Alternatively, we can express the net present lifetime CO₂e per subscriber equivalently as 5,002.4 pounds (2.4 tons). It is worth noting that, in general, an existing tower is available approximately 75% of the time, and thus new construction is not always necessary. This percentage is factored into the CO₂e cost per tower per subscriber.
Summary
The environmental impact of deploying broadband differs significantly based on the technology employed. When comparing fiber to a next-generation fixed wireless solution like Tarana’s G1, the G1 solution is 55% less in cumulative CO₂e emissions per subscriber and 70% less in net present CO₂e emissions.
|
Technology |
CO₂e Required to Deploy |
CO₂e per Subscriber |
Net Present Lifetime CO₂e per Subscriber |
|
Fiber |
30.6 tons per mile |
8.7 tons |
8.3 tons |
|
ngFWA |
29 tons per tower |
4.0 tons |
2.5 tons |
While there is a place for both fiber and ngFWA in broadband deployments, ngFWA emerges as the more environmentally friendly choice. This study underscores the profound impact that broadband choices can have on the environment, with lasting consequences for decades to come.
If you just can’t wait to learn more, check out our other blogs or some of our favorite customer links. Or reach out to us at info@taranawireless.com. We’d love to hear from you.
Input Values
The following assumptions are used for input values in the calculations used here.
|
Metric |
Value |
|
17.1 lbs. |
|
|
22.5 lbs. |
|
|
19.4 lbs. |
|
|
0.8 lbs. |
|
|
CO₂E NCX model discount rate |
3.3% |
|
31.8 gph |
|
|
25.4 mpg |
|
|
500 feet |
|
|
Average fiber length per subscriber |
0.25 miles |
|
Average subscribers per optical line terminal (OLT) |
1,024 subscribers |
|
Average subscribers G1 base node (BN) |
150 subscribers |
|
Average subscribers per G1 tower |
600 subscribers |
|
Power consumed by optical network terminal (ONT) |
10 watts |
|
Power consumed by BN |
275 watts |
|
Power consumed by G1 remote node (RN) |
35 watts |
|
Availability of existing ngFWA vertical assets |
75% of time |
|
Lifetime of broadband subscriber |
30 years |