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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>IoT platform for automated CO₂ measurement and direct</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Nataliia Dziubanovska</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vadym Maslii</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Manager, Schneider Electric's EcoStruxure</institution>
          ,
          <addr-line>Johnson Controls' Metasys, Honeywell Forge, and IBM</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>West Ukrainian National University</institution>
          ,
          <addr-line>11 Lvivska Str., Ternopil, 46009</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2026</year>
      </pub-date>
      <abstract>
        <p>This article presents a proof-of-concept IoT platform for automated CO₂ emissions monitoring and direct carbon quota calculation at the software level. Instead of physical sensors, a Python-based digital twin was developed to generate synthetic ppm data incorporating sinusoidal oscillations, random noise, and linear drift. The raw values undergo two-point calibration (a = 1.02; b = -5) and are converted to tonnes per hour using the density of CO₂. To assess accuracy, an “ideal” noise- and drift-free sinusoid is generated and compared against the calibrated measurements. The primary purpose of this work is therefore not limited to channel emulation but to validate the feasibility of an end-to-end IoT pipeline covering the entire data lifecycle - from data generation and calibration to quota calculation and registry integration. While the present model is limited to CO₂ as a baseline indicator, it establishes a solid foundation for future extensions toward multi-component mixtures and adsorption dynamics. The results confirm the viability of the proposed “generation → processing → quota calculation → registry” architecture and provide a basis for integration with real IoT devices, MQTT/REST networking protocols, and the national emissions trading system.</p>
      </abstract>
      <kwd-group>
        <kwd>IoT</kwd>
        <kwd>digital twin</kwd>
        <kwd>CO₂ monitoring</kwd>
        <kwd>calibration</kwd>
        <kwd>emissions quotas</kwd>
        <kwd>Python emulation</kwd>
        <kwd>emissions trading system</kwd>
        <kwd>1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        In the era of pervasive digitalization, the Internet of Things (IoT) has emerged as a novel paradigm for
monitoring carbon emissions. IoT can be defined as a network of interconnected physical devices,
instruments, and other objects equipped with sensors and software, all linked via the Internet to
collect, store, analyze, and exchange data and derived insights [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Market forecasts estimate
that the global IoT market will reach USD 445.3 billion by 2025 and soar to over USD 934 billion by
2033 – more than tripling revenue within a decade – while the number of connected IoT devices
worldwide is expected to triple over the same period [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        Contemporary industrial CO₂ monitoring systems primarily rely on Continuous Emissions
Monitoring Systems (CEMS), which cover roughly 70 % of carbon emissions in the power sector [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ],
as well as on comprehensive energy-management platforms such as Siemens’ SIMATIC Energy
Envizi [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. A key component of the European Emissions Trading System (ETS) is its quota-allocation
mechanism, and accurate enterprise-level CO₂ monitoring underpins effective ETS operation and
transparent carbon-quota trading. Although these systems deliver high measurement fidelity and
data collection, their integration with reporting tools (e.g., the EU ETS Reporting Tool) often requires
manual data uploads and does not guarantee real-time quota adjustment. Digital solutions such as
Predictive Emissions Monitoring Systems (PEMS) use historical data to estimate emissions but do not
support fully automated quota calculation and registration, leading to decision-making delays and
increased risk of inaccuracies. N. Ding et al. (2025) emphasize that achieving high accuracy in
lowconcentration CO₂ measurements critically depends on robust calibration and quality-control
mechanisms [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Moreover, traditional monitoring methods exhibit limitations – low accuracy and
sampling frequency, significant hysteresis, and limited reliability [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Ding et al. further highlight
that comprehensive carbon accounting, which is most widespread, demands precise recording of
carbon-footprint activities, a requirement that often exceeds the financial capacity of small and
medium-sized enterprises and is further undermined by human error [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
      <p>Ukraine is currently preparing to implement a national emissions-trading system, as mandated by
its Association Agreement with the European Union. This initiative imposes stringent requirements
on the transparency, timeliness, and reliability of greenhouse-gas reporting. The absence of an
integrated “sensor-to-registry” data transfer mechanism creates a potential gap between on-site
quota calculations and their official verification in the state registry. In response, this work develops
and tests a proof-of-concept IoT platform featuring a Python-based digital twin of the sensor to
generate synthetic CO₂ data, apply two-point calibration, and automatically compute quota volumes
for submission to an experimental “mock” registry. The proposed “sensor → quota-calculation →
registry” architecture demonstrates the technical feasibility of an end-to-end integration model and
provides a foundation for future deployment with physical IoT devices, MQTT/REST protocols, and
national reporting systems in the context of Ukraine’s emissions-trading system.</p>
      <p>The primary purpose of this study is therefore not limited to channel emulation, but to validate a
proof-of-concept IoT pipeline covering the entire data lifecycle – from digital-twin based data
generation through calibration and quota calculation to registry integration.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Literature review</title>
      <p>
        For effective emissions monitoring, intelligent management via the Internet of Things has been
investigated across various sectors – primarily energy, manufacturing, and construction [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
According to the International Energy Agency, carbon emissions from the energy sector in 2022
accounted for approximately 40 % of global emissions, making it the largest industrial source of
carbon output and energy consumption [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>
        A. Arsiwala, F. Elghaish, and M. Zoner (2023) explored pathways to carbon neutrality by
proposing an integrated IoT and AI solution – key components of a digital twin – implemented as an
interactive monitoring dashboard [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. S. Winter et al. (2025) introduced a unified digital-twin
framework and data model that enable seamless, continuous information exchange among all
stakeholders [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>
        Y. Jiang and Z. Mao (2025) note that carbon-emissions monitoring is critical for implementing
reduction strategies, yet excessive reliance on detailed energy data and manual calculations renders
the data-collection process low-frequency, time-lagged, and unreliable. They proposed an
ICEEMDAN-Inception-Transformer model capable of providing accurate hourly carbon-emissions
data collection for energy-sector enterprises [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>Li Qingqing et al. (2024) argue that achieving carbon neutrality requires an efficient, reliable
carbon ecosystem comprising regulatory bodies, emissions-reduction organizations, and
independent auditors. They developed the Modelx+MRV+O system based on IoT and blockchain
technologies [12]. Blockchain and IoT can ensure data integrity, transparency, and immutability,
facilitating the dissemination of carbon credits within the toolkit of emissions-reduction measures
[13], [14].</p>
    </sec>
    <sec id="sec-3">
      <title>3. Methodology</title>
      <p>In our work, we have implemented a software pipeline in pure Python that emulates the complete
CO₂ emissions monitoring data lifecycle – “generation → processing → storage → analysis” (Figure
1). In the first stage, the sensor emulator module produces a sequence of ppm readings by modeling
ambient concentration as a sinusoidal waveform, overlaid with random Gaussian noise and a linear
drift from the initial timestamp. Each data point is tagged with its send time and enqueued into a
Python internal queue, which acts as the sole communication channel between the generator and the
processor.</p>
      <sec id="sec-3-1">
        <title>Sensor</title>
      </sec>
      <sec id="sec-3-2">
        <title>Emulator</title>
        <p>(generation of
raw ppm with
noise, drift,
and timestamps)
Queu
e
(queue)




</p>
      </sec>
      <sec id="sec-3-3">
        <title>Data Storage</title>
        <p>SQLite table ‘readings’</p>
        <p>CSV “mock registry” quotas.csv</p>
      </sec>
      <sec id="sec-3-4">
        <title>Analysis &amp; Visualization</title>
        <p>Calculation of RMSE, MAE, R²
Plots of ppm versus ideal
Latency plot



Processing Engine</p>
        <p>Calibration
Conversion from ppm to
tonnes/hour
Latency measurement</p>
        <p>The sensor emulator generates a series of NUM_SAMPLES (100) observations at a fixed interval
(0.5 s). One hundred measurements provide a statistically significant dataset for metric evaluation,
and the 0.5 s interval allows the full dataset to be collected in 50 s while maintaining sufficient
resolution to capture the waveform and noise.</p>
        <p>For each measurement, the following are computed:
1. The base sinusoid modeling the cyclic variation in concentration is given by:
base = 400 + 200 ∙( sin (t - t 0) + 1),
600
(1)
where t 0 is the start time of the series.</p>
        <p>This value corresponds to ideal_ppm, i.e., ideal_ppm=base. The parameters were selected with the
following considerations:</p>
        <p>400 ppm – the approximate mean background CO₂ concentration in the atmosphere at ground
level.</p>
        <p>±200 ppm – the amplitude of cyclic fluctuations, yielding a wave from 200 to 600 ppm; this
simulates daily concentration changes resulting, for example, from variations in industrial activity or
diurnal photosynthetic uptake by vegetation. This wider span was intentionally chosen to test the
robustness of calibration and to approximate possible variations observed in localized industrial or
environmental settings.</p>
        <p>600 s in the denominator of the sine argument sets the oscillation period to about 10 minutes in the
“accelerated” timescale, allowing many daily-like cycles to be emulated within a short measurement
session.</p>
        <p>2. Random noise, modeled as
noise ~ N (0,10) ppm .
(2)</p>
        <p>A standard deviation of 10 ppm represents a typical level of fluctuation observed in consumer or
semi-industrial NDIR sensors over a single measurement session. This magnitude of noise introduces
sufficient variability without distorting the overall waveform.</p>
        <p>3. Linear drift, defined as
(3)
drift = t - t 0 ∙ 0.1 ppm / day .</p>
        <p>86400
0.1 ppm/day – a small, slow drift typical of NDIR modules caused by temperature variations or
sensor aging. It is divided by 86400 s (24 h) so that each second contributes only a minute offset. In the
accelerated simulation timescale used in our experiment, this drift is proportionally added to each
generated data point, ensuring that long-term sensor instability is represented even within short
measurement sessions.</p>
        <p>As a result, we obtain the final raw ppm value ppmraw = base + noise + drift together with the
send timestamp t send and the elapsed time from the start, re sts = t - t 0.</p>
        <p>In the collector, each “message” is read from the queue, the receive time t recv is recorded, and the
latency is computed as latency = t recv - t send. Calibration is performed using a two-point method:
ppmcorr = a ∙ ppmraw + b,
where a = 1.02, b = - 5.</p>
        <p>These coefficients were chosen to align two anchor points: when the raw sensor reads 400 ppm,
the correction brings it close to the true 400 ppm, and when it reads 1000 ppm, it brings it close to
1000 ppm. A linear regression through these two reference points provides a quick adjustment of the
sensor’s output to a calibrated instrument. This simple linear correction compensates for the sensor’s
systematic bias.</p>
        <p>The corrected ppm values are converted to tonnes per hour using the classical formula:
mkg / s = ppmcorr ∙ ρCO2,</p>
        <p>106</p>
        <p>M t / h = mkg / s ∙ 13060000 .</p>
        <p>kg
The density of CO₂ (1.977 3 ) is the physical value under standard conditions (1 atm, 25 °C). It
m
is used to convert concentration (ppm) into a mass flow rate (kg/s). We then apply a factor of
3600/1000 to convert kg/s into tonnes/hour. This step simulates the transformation of concentration
into a mass emission rate.</p>
        <p>Simultaneously, all processing results are written to a local SQLite database (the readings table for
raw and calibrated ppm values and mass flow) for persistent storage and to a CSV file (quotas.csv)
(4)
(5)
(6)
(7)
acting as a “mock registry” of quotas, thereby simulating integration with the national emissions
trading system.</p>
        <p>In the final step, the analytics module selectively reads the accumulated data, generates an “ideal”
noise- and drift-free sinusoidal curve, and compares it with the calibrated data stream by computing
the root mean square error (RMSE), mean absolute error (MAE), and the coefficient of determination
(R²).</p>
        <p>RMS E ppm = √ N i=1
1 ∙ ∑N ( ppmcorri - ideal ppmi)2,
1 N
MAE _ ppm = ∑|ppmcorri - ideal _ ppmi|</p>
        <p>N i=1
N
∑ ( ppmcorri - ideal _ ppmi)2
R2 _ ppm = 1 - N i=1
∑ (ideal _ ppmi - ideal _ ppm)2
i=1</p>
        <p>, ideal _ ppm = 1 ∑N ideal _ ppmi</p>
        <p>N i=1
(8)
(9)
(10)</p>
        <p>These metrics enable the assessment of how closely the synthetic data stream matches the “ideal”
by using our noise‐ and drift‐free model based on the same underlying sinusoid but without any
random components.</p>
        <p>At each step, performance (latency) was measured as the difference between the send timestamp
and the in-memory processing time. Concurrently, a latency distribution plot for each message was
generated. The number of sent versus received messages (packet-loss) was also calculated.</p>
        <p>Thus, the methodology encompasses the entire data lifecycle: parameterized data generation,
calibration, quota calculation, validation, and pipeline performance evaluation. This provides a solid
foundation for subsequent integration with real IoT devices and the national emissions trading
system.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Results</title>
      <p>For quantitative evaluation of the accuracy and performance of the developed data pipeline, a series
of identical test runs were conducted in a controlled environment. The obtained results enable a
direct comparison of the system’s behavior with the theoretical model, free from external latency
factors.</p>
      <p>These controlled experiments made it possible to evaluate both the accuracy of the synthetic
sensor emulation and the stability of the processing pipeline. In particular, we examined how closely
the calibrated data follow the ideal sinusoidal pattern and quantified the impact of noise and drift on
the overall measurement quality. This setup also allowed us to assess the end-to-end performance of
the pipeline in terms of latency, packet loss, and statistical error metrics.</p>
      <p>In a 50-second session with a 0.5 s interval, 100 messages were generated and processed. To
compare the calibrated measurements against the reference noise- and drift-free sinusoid, Figures 2–
3 present the plot of ppmcorr versus ideal_ppm and the calculated versus ideal CO₂ emissions in
tonnes per hour.</p>
      <p>As shown in Figure 4, the moving average effectively smooths out high-frequency noise
fluctuations, bringing the measured curve closer to the underlying trend while preserving the overall
rising shape of the concentration. This confirms the appropriateness of applying filtering to enhance
the stability and accuracy of the monitoring algorithm.</p>
      <p>The values of the key performance indicators resulting from the simulation are presented in
Table 1.</p>
      <sec id="sec-4-1">
        <title>Proportion of the ideal signal’s variance explained by the calibrated data RMSE_tonnes/h</title>
      </sec>
      <sec id="sec-4-2">
        <title>Latency_avg</title>
      </sec>
      <sec id="sec-4-3">
        <title>Latency_min / Latency_max</title>
      </sec>
      <sec id="sec-4-4">
        <title>Packet loss</title>
      </sec>
      <sec id="sec-4-5">
        <title>RMSE in tonnes per hour; approximately equivalent to ~9 ppm at the given flow rate</title>
      </sec>
      <sec id="sec-4-6">
        <title>Average in-memory processing latency per message</title>
      </sec>
      <sec id="sec-4-7">
        <title>Minimum and maximum latency, limited by Python’s timer resolution</title>
      </sec>
      <sec id="sec-4-8">
        <title>No messages lost; all 100 messages processed</title>
        <p>successfully</p>
        <p>This table demonstrates that both the modeling accuracy (RMSE, MAE, R²) and the pipeline
performance (latency and transmission reliability) remain within the bounds of a software-only
emulation. The error distribution (ppmcorr − ideal_ppm) exhibits a mean bias of approximately 0.7
ppm, a median of 1.2 ppm, a standard deviation of 11.1 ppm, a minimum of –25.4 ppm, and a
maximum of +29.8 ppm. All 100 messages were processed without any loss (packet loss = 0%) and
with effectively zero latency (avg/min/max latency ≈ 0.000 s), underscoring the instantaneous
inmemory processing of the Python script.</p>
        <p>Figure 5 shows the distribution of processing latency for each of the 100 messages.</p>
        <p>As shown in Figure 5, all points lie on the zero line (within the resolution of Python’s timers),
further confirming truly instantaneous in-memory processing without any real delays.</p>
        <p>These results demonstrate an acceptable level of accuracy for the POC pipeline and its readiness
for subsequent deployment with real networking protocols and sensors.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Discusion</title>
      <p>The results make it clear that our software-only emulation of the end-to-end pipeline – from sensor
to quota calculation – achieves the desired measurement accuracy and instantaneous data
processing, while also highlighting several key areas for future work.</p>
      <p>Although the sinusoidal model with added Gaussian noise and linear drift effectively mimics the
basic behavior of NDIR sensors, actual devices are subjected to a far broader range of environmental
and operational disturbances – temperature swings, humidity, particulate contamination, and
electromagnetic interference. In real-world deployments, it will therefore be necessary to implement
multi-point calibration or adaptive filtering techniques to correct accumulating errors.</p>
      <p>The zero latency observed in our in-memory prototype demonstrates that pure software
processing introduces no appreciable delay, but integrating a network layer (whether MQTT or
REST) will inevitably add transit delays that depend on link quality and broker load. Industrial
practice generally tolerates latencies of 1–2 seconds, so the next step should be to construct a testbed
with emulated brokers and measure how these metrics evolve when the system scales to several
dozen devices.</p>
      <p>Integration with Ukraine’s national emissions trading system (ETS) will require not only a robust
data channel but also end-to-end message authentication, encryption, and auditability. A simple API
key may be insufficient; public-key infrastructure (PKI) or even a distributed ledger (blockchain)
could be considered to guarantee data immutability and trust.</p>
      <p>Finally, the economic feasibility of such an automated pipeline must be assessed by weighing the
deployment costs of sensors and supporting infrastructure against the time savings and error
reductions in reporting. For small and medium-sized enterprises, bundling the core “software +
digital twin” solution with outsourced calibration and maintenance services may lower the barrier to
adoption.</p>
      <p>It should be emphasized that the present proof-of-concept model is intentionally limited to CO₂ as
a baseline indicator to validate the feasibility of an end-to-end IoT pipeline for automated quota
calculation. In real industrial and environmental conditions, emission streams typically contain
multi-component mixtures such as CO₂, CH₄, NOₓ (primarily NO and NO₂), and volatile
hydrocarbons, and are subject to competitive adsorption, diffusion, and multiphase equilibrium
processes. These phenomena significantly influence both the composition and the effective
concentration of emissions. Future research should therefore extend the proposed platform by
integrating multi-component models and adsorption dynamics, as highlighted in recent studies on
CO₂/CH₄ interactions [15], adsorption modeling on activated carbon [16], and advances in CO₂
capture by absorption and adsorption [17]. Incorporating these aspects will considerably broaden the
applicability of the IoT-based monitoring pipeline and make it more representative of real-world
scenarios.</p>
      <p>In summary, these preliminary findings validate the concept and raise several practical questions
– how to adapt the algorithm to real sensors, how to secure a reliable transmission channel and
comply with regulatory requirements, and how to develop a cost-effective service model under
Ukraine’s ETS. This work thus provides a springboard for subsequent field trials, large-scale
deployments, and full integration with physical IoT hardware and national registry systems.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion</title>
      <p>The experimental results validate the effectiveness of the proposed “sensor → processing → storage
→ analysis” pipeline implemented entirely in software. By employing a Python-based digital twin
that generates a sinusoidal baseline overlaid with Gaussian noise and a slow linear drift, we achieved
a root-mean-square error (RMSE) of approximately 9 ppm and a coefficient of determination (R²) of
about 0.29 following two-point calibration. The complete absence of message loss and the near-zero
in-memory processing latency demonstrate the extraordinary speed and reliability of the internal
data pipeline.</p>
      <p>This proof-of-concept platform lays a solid foundation for further practical and experimental
work – especially in light of Ukraine’s forthcoming national emissions trading system (ETS), which
demands stringent data timeliness and accuracy. The architecture supports field trials with actual
NDIR sensors, encompassing temperature- and humidity-dependent errors and multi-point
calibration schemes. Future development will extend the pipeline to real-world deployments by
integrating MQTT/REST protocols (introducing realistic network latencies and risks), porting
computational modules to microcontrollers, and establishing a secure transmission channel with
authentication and encryption for direct ETS registry uploads. Careful economic modeling of
platform maintenance and calibration services for small and medium-sized enterprises will be
essential to ensure accessibility and cost-effectiveness under resource constraints. In sum, the
proposed software pipeline represents a crucial stepping stone toward a full-scale IoT platform for
automated CO₂ monitoring and direct quota calculation within state registries.</p>
      <p>At the same time, we acknowledge that the present proof-of-concept is limited to CO₂ as a
singlecomponent indicator. In real industrial conditions, emission streams contain multi-component
mixtures and are affected by competitive adsorption and multiphase equilibrium. Addressing these
phenomena in future versions of the platform will further increase its applicability and bring the
IoTbased pipeline closer to real-world deployment.</p>
    </sec>
    <sec id="sec-7">
      <title>Declaration on Generative AI</title>
      <sec id="sec-7-1">
        <title>The authors have not employed any Generative AI tools.</title>
        <p>[12] Li Qingqing at all. (2024). An efficient tool for real-time global carbon neutrality with credibility
of delicacy management: A Modelx+MRV+O system. Applied Energy. Vol. 372, 123763.
https://doi.org/10.1016/j.apenergy.2024.123763.
[13] Brunnermeier Markus K., Oehmke, Martin. (2013). The maturity of the financial system. Journal
of Finance. 68 (2), 483-521.
[14] Boumaiza Ameni, Maher Kenza. (2024). Harnessing Blockchain and IoT for Carbon Credit
Exchange to Achieve Pollution Reduction Goals. Energies. 17 (19), 4811.
https://doi.org/10.3390/en17194811.
[15] Asif, M., Wang, L., Naveen, P., Longinos, S. N., Hazlett, R., Ojha, K., &amp; Panigrahi, D. C. (2024).</p>
        <p>Influence of competitive adsorption, diffusion, and dispersion of CH4 and CO2 gases during the
CO2-ECBM process. Fuel, 358, 130065. https://doi.org/10.1016/j.fuel.2023.130065.
[16] Mo, Z., Li, M., Sun, S., Zhu, R., Zhan, D., Li, A., ... &amp; Yu, Q. (2024). Modeling of activated carbon
and multi-scale molecular simulation of its water vapor adsorption: A review. Journal of
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      </sec>
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