Author: Thierry LEBOUCQ

Thierry LEBOUCQ is the chairman of GREENSPECTOR, which he founded in 2010. Author and speaker, he is extremely active and plays a pioneering role in the green information technology sector in France. He was a major contributor in France and in Europe to software ecodesign concerns. He has led several R & D projects on green software and several initiatives on green labeling for Web, mobile and IoT applications.

Nantes Digital Week 2022: Ranking of the digital sobriety of partners’ and visitors’ websites

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Last month we were present at the Nantes Digital Week. We participated in several conferences and workshops on the theme of responsible digital. It was an opportunity to meet many digital actors but also many visitors curious to know more about this vast subject.

On Thursday 22 October we ran the workshop “Hosting, measuring and designing virtuous websites” together with DRI and Webofacto. In this context, we measured the websites of several visitors and partners of the event.

The ranking in detail

The average carbon impact of one minute of navigation for these 98 partners is 0.45 gEqCO2, which is the equivalent of driving 2 metres in a petrol-driven car. Only 8 sites are above this average, which shows a good trend. The most sober website in this ranking (the CIC site, 0.19 gEqCO2) has 7.8 times less impact than the least sober site (Saint-Nazaire Tourisme, 1.5 gEqCO2).

The average power consumption (mAh) is 3.7 mAh and on average 9.01 MB of data is exchanged. In terms of web requests, the average is 73.

RankNameecoscoreCarbon Impact (gEqCO2)requestsEnergy (mAh)Data (Mo)Memory (Mo)Water footprint (Litres)Surface footprint (m2)
2Le Blog du Modérateur840,2183,571,06605,540,030,40
3La Cantine800,22383,21,34570,440,030,37
4Banque des territoires730,22512,921,31669,140,030,35
7Chateau des Ducs de Bretagne620,27483,91,91757,640,040,45
8BNP Paribas720,28773,122,11669,860,040,39
15PALO IT610,39873,85,04708,840,050,47
16Université de Nantes710,4613,468,16650,390,050,42
18La Box Loire Atlantique630,47913,748,63650,420,060,47
19Radio Prun'500,48443,5612,92712,560,050,43
20Maison Europe580,5514948,09695,450,070,53
21Isefac Bachelor410,61813,828,4915,640,070,53
23Tele Nantes480,81463,4321,39821,120,080,48
24Groupe Onepoint571,11843,3640,15744,130,100,47
25Saint Nazaire Tourisme471,5704,1658,42761,910,130,57

For each of these websites and applications measured on a Samsung Galaxy S9 smartphone, the measurements were carried out using our Greenspector Benchmark Runner tool, which enables automated testing.

  • Loading the application
  • Reading the website in the foreground
  • Reading the page with scroll
  • Website inactive in background

Each measurement is the average of 3 homogeneous measurements (with a low standard deviation). The consumption measured on the smartphone connected to a wifi network may be different when the smartphone is connected to a wired network. For each iteration, the cache is emptied beforehand.

Find out how Greenspector assesses the environmental footprint of a digital service.

What resources should be reduced in the context of good software eco-design practices: Processing on the server-side or on the user side?

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One of the first answers to the question “what resources” is: all! But it is necessary to have a more specific answer because certain practices will favor an economy on the server-side, others on the memory side rather than the CPU. There are winning optimizations for all areas but unfortunately, the behavior of computer systems is more capricious!

The guiding principle is to extend the life of the hardware, whether for the terminal or for the servers. We will see that for environmental gains, reducing energy will also be an improvement axis.

In a previous article, we discussed the need for energy optimization in the case of mobile devices. Today we are trying to answer the question: what architecture to put in place, and in particular to put processing on the user side or on the server-side? 

The answer is: server-side processing to be preferred …

The answer is quite simple: let’s load the servers! Indeed, when we take LCA and impact analyzes, we observe a much stronger impact on the user side (Example with our study on the impact of playing a video). The servers are shared and are optimized to absorb a load. The manager can also manage load fluctuations with Power Capping (peak load absorption while maintaining controlled energy consumption). The lifespan of the servers can also be managed (hardware that can last up to 10 years). Compliance with a Green IT policy can also be better monitored and shared.

Terminals, on the other hand, despite having powerful processors, do not have these advantages. Very little control of the lifespan, no management of the health of the system, fragmentation of powers and therefore of behavior …

… but watch out for resources and scalability

While it is better to put the computations on the server-side, this is no excuse for not maximizing the impact on the server-side. Scalability is possible but must be monitored. Because adding a virtual instance will have an impact on the future need to add a physical machine and therefore will increase the environmental impact.

In addition, limiting power consumption will be necessary because a high demand for power will transfer into an increase in the power consumed on the server rack and higher cooling needs.

And the cost of the round trips of the network round trips in this case?

The question appears on network exchanges if we move calculations to the server-side. This is currently a false problem because there is too much exchange. The network resource and servers being seen as “free” and the architectures going more and more towards the service/microservice, the processing on the user side calls too much the data centers. It will be necessary rather control the number of network exchanges, whatever the choice of architecture.

Is this currently the case in architectural practices?

This has not been the trend in recent years. Indeed, the arrival of powerful user platforms, i.e. with multicore processors and high-performance network connections, have pushed a lot of processing to the user side. Development Frameworks, especially JavaScript Frameworks, made this possible.

However, the trend is starting to reverse. We can notably mention Server-Side Rendering (SSR) with for example next.js or the generation of static blogs with Hugo. We can also see techniques maximizing the use of elements already present on the user’s terminal such as the web browser engine by using CSS rather than JS.

We will try to answer in the next articles: which resources (CPU, memory …) should we optimize as a priority?

Greenspector, an actor of Planet Tech’Care

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What is Planet Tech’Care?

Planet Tech’Care is a platform that connects organizations and training actors who wish to mobilize to reduce the environmental footprint of digital technology with a network of partners, digital and environmental experts.

By adhering to this manifesto, signatories have free access to a support program made up of workshops designed by the initiative’s partners. The platform is run by the Digital Responsible for Syntec Numérique.

Why is Greenspector doubly committed to this national approach?

Greenspector, a member of Syntec Numérique and a company with a mission, is committed both as a signatory of the manifesto and is committed as a partner of this program to support the signatory organizations to take action, act for a sober digital and inclusive. Digital sobriety is a major factor in reducing our impact, but it is also a performance factor. The awareness of digital makers is key in the image that digital reflects today, this infinite world, without barriers and without limits in use. Many want to ignore this impact by looking more at the digital contributions to the reduction of environmental impacts but it must not become this industry which did not know how to react quickly enough as we reproach today to our models of movement, to our food. . Beyond awareness, the Planet Tech Care initiative is a way to mobilize the digital world to engage. The subject of the eco-design of digital services will be a way to reduce the consumption of energy and resources in the use phase but also to reduce the impact of equipment by using it better and by extending its lifespan. life.

A reminder of the key points of the manifesto:

1. Recognize that environmental change is a major issue for humanity on which digital players have an impact and must mobilize:

  • Commit publicly through the signing of the manifesto
  • Disseminate the initiative to their sphere of influence

2. Take action to contribute, at their level, to controlling environmental risks

  • Measure the environmental footprint (at minimum carbon) of their digital products and services
  • Identify and implement actions to reduce their environmental impacts
  • Identify and implement actions to extend the lifespan of digital products and services
  • Share this information and procedures with the stakeholders concerned

3. For those involved in education or offering training, set up training modules or courses to develop the skills of students and employees in responsible and environmentally efficient digital.

The challenges of eco-responsible digital technology for the public sector

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Public organizations have particular challenges when it comes to digital eco-responsibility. Like private organizations, they respond to a global challenge to limit the environmental impacts of digital services, which are growing as much as public services are modernizing and rapidly becoming computerized.

This subject, like accessibility to the greatest number of people becomes a subject of exemplary nature for public services which, we hope, will have a vocation to have a capacity to train private organizations and more generally society at large. Eco-responsibility has appeared several times in the political sphere since we see elected officials who seized on the subject at the same time as political dissident movements integrated this dimension of eco-responsible digital. As a sign of this enhancement and of the new speeches / political programs, we now have an elected representative in Responsible Digital for the city of Nantes (France).

Beyond the environmental issue, digital sobriety also helps to reduce the digital divide, allowing equal opportunities for online content and services since a more frugal service will also be more accessible to citizens with limited or limited connection. an old-tech, low-tech or cluttered computer / mobile.

An acceleration is underway for the consideration and will become even more visible since article 55 of French Law n ° 2020-105 of February 10, 2020 relating to the fight against waste and the circular economy »Specifies that organizations must promote in the markets software whose energy consumption is limited during the use phase.

As of January 1, 2021, the State services as well as the local authorities and their groups, during their public purchases and as soon as possible, must reduce the consumption of single-use plastics, the production of waste and prioritize goods resulting from reuse or which incorporate recycled materials by providing useful clauses and criteria in the specifications.
When the acquired good is software, the administrations mentioned in the first paragraph of article L. 300-2 of the code of relations between the public and the administration promote the use of software whose design makes it possible to limit the associated energy consumption. to their use.

A digital eco-responsibility approach is a quality approach that comes at a cost

This constraint beyond the gain it brings also represents a cost because it requires integrating this eco-design approach into the manufacturing process and thus training the teams in the production chain in good practices, reflexes but also to measure, analyze, detect over-consumption and therefore spend time controlling, measuring, sometimes correcting; All the more so since this approach must take place beyond its initial manufacture but also during the maintenance phase in a context of technical developments often undergone and functional adjustments.

Should a Project Owner (MOA) expect its Project Manager (MOE) partner to integrate this approach spontaneously? Today no, as this approach comes at a cost, it is often risky to integrate this qualitative dimension without taking the risk of drifting or losing the market for a MOE candidate. The MOA must in this case integrate REQUIREMENTS from its specifications which must allow to qualify the expected “quality”.

The project management of the development project – maintenance of its application heritage must be fixed – and set for these partners (MOE, AMO, COM teams, …) – objectives = REQUIREMENTS

But how to integrate these requirements in the clauses of the contracts, how to manage them and how to verify them?

We can read some requirements:

  • The candidate must demonstrate in his response, his level of maturity of his CSR approach in his activities
  • The candidate will have to demonstrate his ability to integrate the digital eco-design dimension in his response
  • The candidate will have to propose / integrate good eco-design practices for websites

Often awkward or superficial, digital eco-responsibility requirements must be more precise and be oriented towards results objectives rather than means requirements.

What type of requirement?

Results requirements have several advantages over good practices (means requirements) because they absolutely validate that the result is good or not good without an expert debate, without a debate on the applicability of a rule, partial application or not, correct implementation or not.

They are above all not very dependent on technological developments and have the advantage of remaining on intermediate indicators that are easy to collect and are easily verifiable and measurable.

However, they must be accompanied by a repository of best practices, in the appendix, to avoid putting in place corrective actions to optimize after the fact. It is also a good way to involve the design and development teams in the process. These attached documents should not be too heavy and focus on generic standards, not techno or language oriented.

They have 2 complexities: they must be calibrated to set thresholds and they do not transfer all responsibility for the result to the person who “manufactures” (MOE).

What metrics to measure to cover the major impacts of a digital service?

A high level indicator comparable to other areas is the carbon impact expressed in geqCO2. The advantage of this indicator is that it is universal and can be shared by everyone in the company, with its customers, comparable with its competitors, in its ecosystem, with any service / product.

The carbon impact is not a measurable indicator but “projectable” on the basis of flow or intermediate indicators. These include energy consumption, network data consumption, display performance or the number of requests to servers internal or external to the organization.

In any case, the Carbon projection will be all the more reliable if we start from real measurements on real devices than from estimation or measurement on an emulator. This projection can be improved by knowing the routes or the type of material on which the service or the content is used.

How to set thresholds for a result requirement?

Setting thresholds first requires specifying the conditions under which measurements such as:

  • The technical conditions of the measurement: on a device type, on a wired / mobile / wifi type of connectivity, on a given browser, etc.
  • Adjustment parameters: with such brightness, with an empty cache or not,….
  • The use case that can be compared to a functional unit: one or x pages played over a given time, one or x steps, a journey from A to Z.

Setting thresholds also requires benchmarking one’s domain or existing sound in order to understand the values. By fixing such a value, we answer the 2 questions, am I in values of good qualities and are they attainable?

Means objectives can be added as appendices to the results requirements. A repository of good practices will have a positive impact and allows the MOE teams to get it right the first time without additional correction costs, but be careful, these repositories of good practices or Green Patterns must be instantiated by technology or by languages and therefore evolve over time. pace of technological change or remain very generic.

Example 1 of requirement on the result:

The reference environment is a mid-range tablet, with a Wi-Fi type connection, based on an environment …, on the 5 key routes of my web application made up of X steps, X screens, we set 4 requirements of resources. Each step must not consume more than X KB AND each step must not consume more than X times the power consumption of a blank page AND each step must display in less than X seconds based on the last element loaded AND each step should consume less than X MB of memory.

Example 2 of requirement on means:

The candidate will have to demonstrate his ability to measure / manage his indicators during the project and alert to a deviation in this consumption as quickly as possible during the project.

Example 3 of requirement on means:

The candidate must integrate good development practices at a minimum (annexed to the technical document). 

Validate compliance with a requirement in a project

Once the requirements have been set, they must then be managed during the project via intermediate points which make it possible to probe a partial result and thus avoid the tunnel effect. All these intermediate reviews make it possible to develop automatic scripts which will allow measurement to be carried out in a reliable and comparable manner and to be able to consolidate the test heritage over time. These views also make it possible to adjust if necessary and discuss over-functional or over-content or additional on-board intelligence costs between MOA and MOA.

It is in this validation phase that the result requirement finds its full meaning since we do not need to audit all screens / pages on a repository of good practices but just automated scripts during the project which are replayed on the finished product.

Auxylium: renewed trust for the continuation of the project

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The DGA and Atos renew their confidence in the GREENSPECTOR solution for 2020-2021 on the Auxylium project.


Auxylium is the smartphone project that equips the military in urban areas. It enables it to cope with surveillance and intervention missions, particularly in the context of major situations or events requiring the deployment of forces on the ground in France (SENTINELLE project). In this context, energy control with good usage performance for the best autonomy in the field is a key subject for the successful completion of the mission without weighing down the military’s equipment with additional batteries.

Greenspector will thus be involved in the continuous integration of the project, which will allow Atos teams to control the energy and resource consumption of the application.

Measurement and analysis actions in the previous phases of our collaboration made it possible to detect points of application over-consumption and made it possible to go from 3 hours to 11 hours of autonomy on the main uses.

Greenspector joins the Atos Accelerator program: #AtosScaler

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Greenspector joins the Atos Scaler

GREENSPECTOR joins the ATOS Scaler to pursue initial collaborations with the ATOS Group. The objective of this partnership is the integration of GREENSPECTOR solutions and expertise within ATOS projects to make the applications developed within the framework of the Group more efficient, inclusive and eco-responsible.

GREENSPECTOR is part of a global group of 14 start-ups when the Scaler Atos was launched on July 7, 2020. Greenspector will aim to participate in the “Decarbonization” of the Group’s activities. Recall that ATOS is the first ESN “Digital Services Company” on a global scale to integrate strong objectives of “0 Emission – Net” with the announced intermediate objective of halving their emissions within 10 years.

GREENSPECTOR has collaborated on several projects. We can cite in particular the military project AUXYLIUM (SENTINEL operation) a business application for which joint work with ATOS teams has made it possible to divide by more than 3 the energy consumption on board a smartphone.


This ATOS Scaler selection allows us to pursue a deeper stage in industrial and commercial terms of our partnership in France but also internationally. It responds to the challenges that the ATOS Group has set itself in terms of impact reduction of digital activities for their customers. We are therefore very proud to be able to make our contribution to this virtuous and necessary objective and to develop our international collaborations with a leading and committed ESN

This international partnership is part of a context where digital technology is consuming more and more with a global impact estimated at 4% of GHG emissions but which is growing faster than other sectors with the advent of increasingly frequent uses. and expensive, and increasingly new technologies.

The main figures of the carbon impact of e-commerce in France

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E-commerce sites are high traffic sites (11 million per month) and therefore have an impact reinforced by the volume of use and significant time of use (visit> 5 minutes). In addition, driven by strong growth in e-commerce, longer journey times and more and more mobility, oversized infrastructures to ensure a good level of response time, the e-commerce site makes an ideal candidate for a Carbon assessment of a digital service with environmental responsibility associated with mass services.


The assessment scope is based on the impact of the 100 most visited sites in France over the second half of 2019. It is therefore not exhaustive since the calculations do not take into account all the e-commerce sites with lower traffic.

How to assess the Carbon Impact of an e-commerce site?

To know the Carbon impact of an e-commerce web service, we worked on a simplified method based on real measurements.

On the Datacenter and Network side, we project the Carbon Impact from the consumption of data exchanged with the device (OneByte method of the ShiftProject).

On the User device, a real measurement on a mid-range Android smartphone equipped with a Chrome browser is launched 3 times and averaged before being projected with a Carbon impact factor taking into account the following assumptions: WiFi mix – GPS network, 50% brightness, phone battery wear at 500 full charge/discharge cycles.

The average impact of a course (= 1 visit)

The visit, on average of 5 minutes and 28 seconds on an e-commerce website in France on a smartphone device, has a carbon impact of 2 gCO2eq equivalent to 18 meters traveled by a light vehicle. Or 56 visits to an average e-commerce site impact 1 km driven with an average light vehicle.

The distribution of the sites is fairly homogeneous between 0.5 and 3 grams with some extreme values. Nevertheless, there are large differences: from 0.5 g to 34 g EqCO2, -> ie a ratio of X68 between the 100 Top E-Commerce sites in France. These differences can be qualified by taking into account that the visit time varies by a factor of 5 (from 3 to 15 minutes).

When we project the impacts on monthly visits, an e-commerce website has an average carbon impact of 23.8 Tons CO2eq/month.

The sum of the impacts of the top 100 e-commerce sites is 2380 Tons EqCO2/month, the equivalent of the impact of 21 million km of an average car in France or 531 rounds of the Earth by car or 19,636 average vehicles circulating in France corresponding to the fleet of an agglomeration of 40,000 inhabitants.

Projected over one year, it is 28.6 MegaTons Eq CO2!

Average impact of a page

In order to compare e-commerce sites with each other, the visit time or the number of steps or page views during the visit must be isolated. To do this, we go back to the basic measurement of a page for 1 minute.

A page from an e-commerce website in France has an average impact of 0.36 g CO2 eq.

In simple projection: 1,000 pages viewed for 1 minute on an average smartphone have an average carbon impact equivalent to 3.2 km from a light vehicle. The detailed ranking of the Top 100 e-commerce websites is available here. It will be likely to vary during future updates or request for re-measurement.

Breakdown of sites visited

Large difference: from 0.5 g to 34 g EqCO2, i.e. a ratio of X 68 between the 100 top e-commerce sites in France.

To explain this significant variation in impact, we can note that:

  • The data consumption ranges from 0.6 MB to 55 MB, or a ratio of X 92, this is the most discriminating factor explaining the differences in impact.
  • the energy consumption on the mobile device varies by a factor of 4.7

It is the network part that has the most impact with a share of 69% of the average impact of an e-commerce site on mobile.

If the mobile were replaced by a PC with a wired connection, the “User workstation” part would be much more important. This distribution of impact of course varies with the e-commerce site.

Low impact website case

Compliance with best practices on the network and low consumption on the device

Eco score Greenspector: 81/100, best Eco score of the Top 100 E-Commerce

Equivalent of 161,675 km of a light vehicle for 24.5 million visits / month (Source: Similarweb S2 2019)

Heavy impact website case

No respect for best practices on the network and high consumption on the device

Eco score Greenspector: 21/100, the lowest Eco score of the Top 100 E-Commerce

Equivalent to 44,582 km of a light vehicle for 2.1 million visits/month.

More impactful categories of sites than others?

A ratio of 1 to 3 on the impacts per page between categories

We have about 3 times more carbon impact by browsing a fashion e-commerce site than on an Automotive or Leisure site.

Rq: a single site classified in the Good Plans category

Projected earnings:

If all the sites were aligned with the most virtuous site in our measurements, we could save over a full year:

  • 15,177 tonnes of CO2eq, more than half of the impacts
  • Or 53% reduction in carbon impact
  • The equivalent of 4050 rounds of the earth by car

The major levers for improvement:

E-commerce websites can reduce network volume

  • Adapt content to device / type of connection & connection quality
  • Compression of rich content
  • User cache to avoid content already loaded on a previous visit
  • Limit the number of requests (internal, advertising, external services, etc.)
  • Beware of unsuitable pre-loads

E-commerce sites that can reduce their energy and battery consumption

  • Allow rapid interaction
  • Reduction in the consumption of scripts in the pages (3D animation, graphic animation, etc.)
  • Reduction of trackers / monitoring
  • External services to be evaluated / optimized
  • Reduced travel time
  • A design / graphics / color to optimize

Correlation analysis of carbon data

Correlation analysis between carbon impact and display performance

By taking 20 values from our sample for which we collected performance data, we can validate that there is no correlation between Carbon impacts and Display performance.

The 2 best performing sites are nevertheless also the least impactful sites

The Carbon indicator is an indicator in its own right for the management of an e-commerce website

Correlation analysis between Impact Carbone and Eco score Greenspector

The estimated Carbon indicator does not take into account other parameters, such as memory consumption, CPU, number of requests, or compliance with good practices, etc.
The Eco score includes both the consumption of resources/energy but also a note on compliance with good practices.

There is a “satisfactory” correlation between the estimated Carbon impact and the measured Ecoscore Greenspector.

Please note, the Carbon indicator does not cover all environmental indicators.

The carbon impact of the Top 100 E-Commerce websites

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Sales made on e-commerce sites are increasing each year, more and more on the go or from a smartphone at home. We have never consumed so much through these web platforms as we do today. A debate persists between the ecological impact of e-commerce in terms of logistics compared to a purchase made in-store. It all depends on certain parameters (delivery time, geographic location of the store, logistical means used, etc.). In addition to this logistical question, there is the environmental impact of digital technology for e-commerce purchases. How can we estimate the part that these online purchases represent in terms of the environmental impact of our life as consumers?

To answer this question on e-commerce in France, we took as a basis the ranking of the largest e-commerce sites in France (Top 100 E-Commerce: E-Commerce Nation & SimilarWeb study) and we add to your asks other sites. We measure the consumption of energy and resources on a mid-range smartphone which allows us to assess the carbon impacts on the entire chain: device (Greenspector methodology), network, and datacenter (OneByte method of the ShiftProject). This evaluation is done on the basis of the home page of the e-commerce site and on the basis of a 1-minute protocol. The Greenspector eco score completes the assessment of the site both by respecting good practices but also by measuring other metrics of resources not assessed in the Carbon impact.

Ranking of the carbon impact of the Top 100 E-commerce websites

PositionWebsiteTotal gEqCO2 per page/minuteEcoscore
Measurement date

Your e-commerce website is not in this ranking, contact-us to take a measurement and appear in this ranking!

Which video conferencing mobile application to reduce your impact?

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Article updated with new measures on StarLeaf, Rainbow and Circuit by Unify on May 19, 2020.
Article updated with new measures on Hangouts and Google Meet on May 4, 2020.
Article updated with new measures on Tixeo and Infomaniak Meet on April 23, 2020.
Article updated with new measures on JITSI and Teams on April 15, 2020.

The current “stay at home” context mechanically increases the use of online collaboration tools, in particular videoconferencing tools. This leads to a pressure on the network and more particularly to a significant load on the servers of each solution. It is therefore important from an efficiency point of view but also an environmental impact one to choose the simplest and most efficient solution.

For this study, we compare 14 videoconferencing applications: Whereby, Webex (by CISCO), Skype, Zoom, JITSI, Microsoft Teams, Tixeo, Infomaniak Meet, Hangouts, GoToMeeting, Google Meet, StarLeaf, Rainbow and Circuit by Unify.

For each of these applications, measured on an Samsung S7 smartphone (Android 8), the following three scenarios were carried out through our GREENSPECTOR Test Runner, allowing manual tests to be carried out over a period of 1 minute:

  • Audio conference only in one-to-one
  • One-to-one audio and video conference (camera activated on each side)
  • One-to-one audio conference and screen sharing

Each measurement is the average of 3 homogeneous measurements (with a small standard deviation). The consumption measured on the given smartphone according to a Wi-Fi type network can be different on a laptop PC with a wired network for example.

Measurement of energy consumption (mAh)

The StarLeaf application consumes the most of all three scenarios. This is due to the fact that the consumption in audio only mode, audio + screen sharing or audio + video is the same. This is a special case of our study. The GoToMeeting application is the least energy-consuming, closely followed by Hangouts, Zoom and Webex.

The energy consumption of all these applications is on average 2.1 times higher when adding video to audio and only slightly higher when adding screen sharing to audio (+14%). It’s not a surprise, avoid sharing with a camera to consume less energy on your devices during your video conferences and save your autonomy and the lifespan of your battery!

Measurement of data exchanged (MB)

GoToMeeting and Webex are the two applications that consume the least data. JITSI and Infomaniak Meet are the ones that consumes the most. Overall and without any surprise we note that the audio scenario is the one that consumes the least data. While the scenario activating both audio + video stream is the most consuming one.

The data consumption of all of these applications is 13 times higher when adding video to audio and almost doubled when adding screen sharing to audio (+77%). It’s not a surprise, avoid sharing video and limit your screen sharing to consume less data on networks in your video conferences!

It should be noted that these significant differences are mainly due to the significant audio-video consumption of the JITSI application with 35 MB transferred in 1 minute compared to 1.13 MB for GoToMeeting! JITSI‘s optimized mode does not reduce this data impact (33.4 MB / minute). Infomaniak Meet based on the JITSI engine meets the same volume anomaly on average and mainly on the audio + video part without improvement with the optimized mode.

Projection of the measured carbon impact data (gEqCO2)

A conference on mobile is 3 times more impactful for the environment when we add video to audio.

The carbon impact projection of all of these applications is on average 3 times greater when adding video to audio and higher when adding screen sharing to audio (+35%). It’s no surprise, avoid sharing video and limit your screen sharing to less impact infrastructure (network, datacenter) and on your devices in the context of video conferences!

Without any surprise, a large part of the carbon impacts are located on the network part (63%) but the impacts part on the device (28%) should not be overlooked!

The JITSI and Infomaniak Meet apps even averages 5.8 times more impact when adding video to audio and 40% more when adding screen sharing.

In the Skype vs Teams battle at Microsoft, the overall results are very close (6%). The Carbon impact is lower for Skype with a lower data impact but higher energy consumption on the mobile than Teams.

Which applications optimize energy and data consumption?

Only Whereby and Webex could be tested on optimization features for the mobile version.

The Whereby application with its “Mobile mode” setting which limits the resolution of the stream as well as other resource consumption optimizations. And Webex thanks to its configuration allowing to deactivate High-definition playback of videos only. Whereby saves 21% on energy consumption on the audio side, 15% on the audio and video side and 3% on the screen sharing side. These gains are nevertheless low considering the results obtained by the application that consumes the most audio and video mode from our panel.

On the Webex side, the gains are barely visible as limited only to the video part. It’s barely 5% gain in the Audio and Video scenario for the energy and carbon impact. The exchanged data is even slightly higher in audio and video mode.

The optimized JITSI application does not improve the data or energy impact. Power consumption is even higher in screen sharing mode in this optimized mode. However, there is a reduction in the data loaded in this optimized but minor mode (11% on average). Same findings for Infomaniak Meet.

The optimization of the TIXEO parameters makes it possible to considerably reduce the impact in audio + video mode and allows it to be classified as the 2nd least impacting application in the panel.

As for the Zoom application, a notification of battery overconsumption appeared several times during the measurements. Although we can optimize the video quality on PC, it does not seem possible to configure this on mobile. Without this optimization, the application becomes the most energy-consuming application in audio + video mode.


  • Promote audio only during your conferences: the video stream will tend to consume much more especially when sharing video via camera.
  • We recommend that publishers provide optimization options to the user and make them as accessible as possible even by default.
  • Prefer videoconferences over travel by car!
  • Comparison for 2 people who talk to each other for 3 hours in video + video (1 gEqCO2 on average per minute) when one of the two made 20 kms (112 g eqCO2 / km in France) round trip for a face-to-face face,
  • In videoconference: 180 * 1 * 2 = 360 gEqCO2.
  • By car: 112 * 20 = 2.4 kg EqCO2. Or 6.7 times more for the physical one-to-one.

Best 2019 Android apps and games ranking by GREENSPECTOR

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Google unveiled the best of 2019 Google Playstore in early December last year. Thanks to the GREENSPECTOR App Mark technology, we are revealing the ranking of these applications according to the App Mark, which assesses applications according to 5 criteria: performance, sobriety, discretion, inclusion and, of course, ecology.

Favorite 2019 applications ranking

At the top of this ranking we find the following three applications: Boosted, 21 Buttons and Omio. Only 1/3 of the applications are below the global ecoscore average. Among the 3 least sober applications of this ranking, 2 are strongly impacted by a zero score on at least one of the key indicators. In fact, the Plant Nanny application presents a score of zero on the ecological side (32 MB of data loaded during our evaluation), for the Curio application, it is the performance indicator which is zero, impacted by the time of application loading more than 23 seconds.

Focus on Boosted vs Music Zen

Here we compare the application with the best GREENSPECTOR App Mark (Bosted) versus the lowest ranked application in this ranking (Music Zen).

Even if the energy consumption is not the strong point of Boosted, MusicZen consumes 2 times more battery than Boosted on an identical route … what not to be “Zen” For its autonomy! Simple explanations: there are many trackers in this application which alters its performance and its sobriety. As a reminder, an added tracker also means an average of 8.5% more resource consumption.

Favorite 2019 games apps ranking

On the podium of the highest ranked game applications, we find: Assassin’s Creed Rebellion, Brawl Stars and Fishing Life. We observe that the last three game applications have a zero score for the ecology indicator. This is explained by two highly high technical criteria: the volume of data loaded as well as the CO2 impact. By the way, gaming applications are also more impactful on average than other applications.

Focus on Assassin’s Creed Rebellion vs Diner Dash Adventures

This time we are comparing the Assassin’s Creed Rebellion application versus Diner Dash Adventures.

To understand everything about these indicators, we invite you to read the following article 5 success keys for your application!