A biogas plant is a living process wrapped in flammable, corrosive, and toxic gas — and much of it runs at sites no one visits daily. Anaerobic digestion only produces gas when the biology stays inside a narrow temperature and chemistry band, and a slug of hydrogen sulfide or a stalled mixer can go from nuisance to hazard in minutes. This guide explains what a biogas SCADA system should actually monitor — digester temperature and pressure, gas flow and composition, H2S safety, CHP and flare status, RNG upgrading, and unmanned remote sites — and how Merobix covers those needs with open protocol drivers, sub-30-second alarming, and a platform you can run in the cloud or fully on-premise.
Biogas plant SCADA monitoring is a supervisory system that continuously collects data from a biogas facility — anaerobic digesters, gas holders, blowers, CHP engines, flares, and gas analyzers — and presents it on a central dashboard with automated alarming. It exists to answer two questions at all times: is the digester biology stable, and is the plant safe? Everything a biogas SCADA system does flows from those two questions.
Unlike a manufacturing line, a digester cannot simply be paused and resumed. The methanogenic bacteria that convert feedstock into biogas are slow-growing and sensitive; push them out of their temperature or pH comfort zone and gas yield collapses for days or weeks while the culture recovers. At the same time, the gas itself is a hazard — methane is explosive, hydrogen sulfide is toxic and corrosive, and both accumulate at sites that are frequently unstaffed. SCADA is how operators keep continuous eyes on a process that is biologically fragile and physically dangerous, without standing next to it. For the broader mechanics of how supervisory control works, our how SCADA works primer is a good starting point; this guide focuses on the biogas-specific picture.
Merobix delivers this capability as one SCADA platform, sold either cloud-hosted and fully managed or deployed on-premise on your own servers or VMs. The same drivers, alarms, dashboards, and historian apply whether the site is a single farm digester, a wastewater-treatment digester complex, or a landfill-gas collection field feeding an upgrading plant.
A biogas SCADA system should monitor the process variables that keep the digester biologically stable and the plant safe: temperature, pressure, gas flow, gas composition, and the run state of every pump, mixer, blower, engine, and flare. Below is the practical monitoring list, grouped the way a plant is actually operated.
Temperature is the single most important variable in anaerobic digestion. Mesophilic digesters run in a band roughly around 95–105°F (35–40°C) and thermophilic digesters much hotter, and in both cases the biology tolerates only a few degrees of drift before gas production suffers. SCADA trends each digester's temperature continuously, alarms on high and low excursions, and — just as importantly — reveals slow trends that a spot check would miss, such as a heating loop gradually losing performance or a cold feedstock batch dragging the vessel down. Catching a downward trend early is the difference between a setpoint tweak and a stalled digester.
Digester pressure protects the vessel and the gas-holding membrane. Both over-pressure (gas produced faster than it is used or flared) and vacuum (gas drawn off faster than it is made, often during CHP demand spikes) can damage the structure, so SCADA watches headspace pressure against high and low limits and alarms before pressure-relief devices or vacuum breakers have to act. On membrane-roof digesters, gas holder level or fill percentage is monitored alongside pressure as a real-time picture of stored gas volume.
Gas flow rate and cumulative volume quantify what the plant is producing and feeding downstream to a CHP engine, boiler, flare, or upgrading skid. Composition is what tells you whether that gas is healthy and usable. An inline gas analyzer typically reports methane (CH4), carbon dioxide (CO2), oxygen (O2), and hydrogen sulfide (H2S); SCADA trends each and alarms on the meaningful ones — falling methane (a sign the digester is off), rising oxygen (an air ingress or a safety concern), and rising H2S (covered on its own below). Together, flow plus composition let an operator see production and quality on one screen instead of two instruments in a gas skid.
The mechanical side of the plant keeps the biology fed and homogeneous. SCADA monitors feed and recirculation pump status and runtime, mixer run states (a stopped mixer leads to stratification, crusting, and dead zones), blower and gas-boosting equipment, and foam or overfill conditions where instrumented. Runtime accumulators feed maintenance scheduling, and a mixer or pump that trips at an unstaffed site becomes an immediate alert rather than a discovery on the next visit.
Most biogas plants either burn gas for combined heat and power (CHP) or flare it when it cannot be used, and both are safety-critical endpoints for the gas. SCADA monitors CHP engine status and load so operators know how much gas the plant is consuming and whether the engine has tripped — a tripped engine that goes unnoticed backs gas up into the digester. Flare status matters just as much: a flare that fails to light while gas keeps flowing is both an emissions and a safety event, so a no-flame condition is one of the highest-priority alarms a biogas SCADA system can raise.
The unifying rule for biogas alarms: loss of communication from any skid, analyzer, or remote digester should itself be an alarm. At an unstaffed site, an instrument that goes silent may be an instrument that has failed — and silence is exactly the condition that hides a developing hazard. Merobix treats comms-loss as a first-class alarm delivered by SMS and email, not a quiet gap on a dashboard.
Hydrogen sulfide (H2S) is toxic to people and corrosive to engines, pipes, and instruments, so continuous H2S monitoring is one of the highest-value functions a biogas SCADA system performs. Raw biogas can carry H2S at concentrations that are dangerous to breathe and destructive to a CHP engine's oil and internals, which is why plants scrub, dose iron salts, or add air/biological treatment to knock it down — and why they need to know, in real time, whether that treatment is working.
SCADA reads the H2S concentration from an inline gas analyzer, trends it, and fires an immediate alarm when it crosses a configured threshold. That gives operators time to divert or flare gas, increase scrubbing or dosing, or restrict site access before levels endanger staff or the engine. Because Merobix delivers alarms by SMS and email in under 30 seconds and logs every reading to the historian with a timestamp, the plant gets both fast notification and the defensible record that safety and environmental reviews expect. H2S is also a slow, expensive killer of equipment: trending it over weeks shows whether media is exhausting or dosing is drifting, turning a reactive scramble into planned maintenance.
Renewable natural gas (RNG) plants add an upgrading train that strips CO2, H2S, moisture, and trace components until the product meets pipeline-injection or vehicle-fuel specification — and that train needs the same monitoring discipline as the digester. Upgrading systems (membrane, pressure-swing adsorption, water or amine scrubbing) are run by a PLC and instrumented with analyzers that report product-gas methane purity, and an off-spec batch can mean rejected gas or a pipeline that stops accepting the injection.
Merobix connects to those controllers and analyzers with its standard protocol drivers, so an RNG operator can trend product methane purity, monitor compressor and skid status, and alarm on off-spec or trip conditions on the same platform that watches the digesters feeding the train. This is a generic, protocol-driven monitoring capability — Merobix reads any device that speaks a supported protocol; it is not a pre-packaged RNG product, and each upgrading plant is scoped to the specific equipment on site. The interconnection points and metering on an RNG project make continuous, timestamped data particularly valuable, both operationally and for the record-keeping these projects live on.
Yes — remote, unmanned monitoring is one of the main reasons biogas operators deploy SCADA in the first place. Digesters sit on farms, at landfills, and at wastewater plants that are rarely continuously staffed, and driving to each site to read a gauge does not scale. SCADA replaces the rounds: it reads the site's PLCs, RTUs, analyzers, and flow meters, moves the data to a central platform, and pushes alerts to on-call staff the moment something is wrong.
With Merobix, that data is reachable from any browser or phone, so one operator can watch several digesters at once and get an SMS within seconds of a high digester temperature, a stalled mixer, a flare that failed to light, or a communication dropout. Cloud-hosted deployments are the natural fit for scattered sites on cellular connections and are typically live in three to five days. Where a site or fleet requires it, the same platform runs on-premise and can be fully air-gapped — the choice is about connectivity and data-control policy, not about switching products. For the wider pattern of watching distributed field assets, see our guide to remote monitoring of industrial equipment.
Biogas plants are multi-vendor by nature — a digester controller from one supplier, a gas analyzer from another, a CHP engine with its own controls, and flow meters from a third — so the protocol layer is where a monitoring project succeeds or stalls. Merobix ships 20 protocol drivers across 7 families, which covers the interfaces found on essentially all of this equipment.
The practical point is that Merobix reads existing equipment as it is, without reprogramming the digester controller or CHP package. Because these are open, device-agnostic protocols, any Modbus, OPC UA, or EtherNet/IP device — a plant controller, a gas analyzer, a turbine or engine controller — presents its data the same way. If you are new to the most common of these, our plain-English Modbus guide explains it without jargon.
The right deployment model depends on the site's connectivity, staffing, and data-control requirements — and because Merobix is one platform sold both ways, choosing does not lock you out of the other. Cloud-hosted SCADA is managed by Merobix, needs no on-site server, goes live in three to five days, and lets operators watch every digester from a browser; it is the usual choice for distributed and unmanned biogas sites. On-premise SCADA runs on the plant's own servers or VMs, can be fully air-gapped, and keeps all data on site for operators with strict data-residency or network-isolation policies.
| Consideration | Cloud-Hosted (Managed) | On-Premise (Your Servers/VMs) |
|---|---|---|
| Best fit | Distributed, unmanned, cellular-connected digesters | Air-gapped sites, strict data-residency policies |
| Infrastructure | No on-site server — Merobix hosts and maintains it | Runs on your own hardware or virtual machines |
| Time to live | Typically 3–5 days | Architecture-dependent (your infrastructure) |
| Data residency | Hosted by Merobix | Full residency — data never leaves your network |
| Remote access | Any browser, any device | Per your network policy |
| Who maintains it | Merobix | Your team, with Merobix support |
A fleet operator can run cloud on remote farm digesters and on-premise at a flagship plant with air-gap requirements, all on the same platform and team. For the full architectural trade-off beyond biogas, read our cloud SCADA vs on-premise SCADA comparison.
Merobix connects to the control infrastructure already installed at a biogas plant — digester controllers, gas analyzers, CHP and flare packages, flow meters, and pump and mixer starters — over the open protocols above, without modifying the existing programs. The platform ships with a 99.9% uptime SLA on cloud plans, sub-30-second SMS and email alarming, and an unlimited-retention historian so temperature, pressure, gas-flow, and H2S data are trended and available for operational review and reporting.
Plans scale from Starter, Professional, and Enterprise tiers. Enterprise adds hot standby redundancy, enterprise authentication (LDAP/SAML/RADIUS/FIDO2) and SIEM integration, historian federation for multi-site fleets, and connectors to business systems such as SAP, Maximo, ServiceNow, and PagerDuty — useful when biogas monitoring has to feed a larger maintenance or compliance workflow. Merobix also does Siemens and Allen-Bradley PLC programming and builds UL 508A and C1D2-rated control panels in Texas, so a plant that needs field controls and hazardous-location panels alongside monitoring can get all of it from one team. Pricing is custom-quoted to the plant — there are no per-tag, per-client, or per-protocol fees to model. Security-minded operators should review the security architecture before deploying, and you can size the payback of continuous monitoring with the ROI calculator. To see why operators consolidate monitoring, PLC work, and panels under one vendor, read why Merobix.
Bottom line for biogas operators: pick a platform that monitors the biology and the safety gas with equal seriousness, alarms fast enough to matter at an unstaffed site, speaks the open protocols your mixed equipment already uses, and can run wherever your data-control policy requires. Merobix does all four on one platform — request a demo and bring your digester, gas-skid, CHP, and RNG equipment list.
Biogas plant SCADA monitoring is a supervisory system that continuously collects data from a biogas facility — anaerobic digesters, gas holders, blowers, CHP engines, flares, and gas analyzers — and presents it on a central dashboard with automated alarming. It tracks the parameters that keep a digester biologically stable and the plant safe: digester temperature and pressure, biogas flow, methane and hydrogen sulfide (H2S) concentration, CHP and flare status, and equipment run states. When any value moves out of a safe band, SCADA sends SMS and email alerts so operators can respond before a process upset, a safety hazard, or lost gas production becomes a bigger problem. Merobix delivers this same capability whether the plant is a single farm digester or a multi-vessel wastewater or landfill-gas site.
A biogas SCADA system should monitor digester temperature (to hold the mesophilic or thermophilic range the biology depends on), digester and headspace pressure (over-pressure and vacuum both threaten the vessel and membrane), biogas flow rate and cumulative volume, and gas composition — methane (CH4), carbon dioxide (CO2), oxygen (O2), and hydrogen sulfide (H2S). Beyond the core process, it should track feed and recirculation pump status, mixer and blower run states, gas holder or membrane level, CHP engine load and status, flare status, and foam or overfill conditions. Loss of communication from any remote skid or analyzer should itself be treated as an alarm, because an instrument that stops reporting may be an instrument that has failed.
Hydrogen sulfide (H2S) is toxic to people and corrosive to engines, pipes, and instruments, so continuous H2S monitoring is one of the highest-value functions a biogas SCADA system performs. SCADA reads the H2S concentration from an inline gas analyzer, trends it over time, and fires an immediate SMS and email alarm when it crosses a configured threshold — giving operators time to divert gas, activate scrubbing or dosing, or restrict site access before levels become dangerous or damage the CHP engine. Because Merobix alarms are delivered in under 30 seconds and every reading is logged to the historian with a timestamp, the plant gets both fast notification and the defensible record needed for safety and compliance review.
Yes — remote, unmanned monitoring is one of the main reasons biogas operators deploy SCADA. Many digesters sit on farms, at landfills, or at wastewater plants that are not continuously staffed, so operators rely on remote visibility and alerts instead of physical rounds. SCADA reads the site's PLCs, RTUs, gas analyzers, and flow meters, transmits the data to a central platform, and notifies on-call staff by SMS and email within seconds of any abnormal condition — a high digester temperature, a stalled mixer, a flare that failed to light, or a communication dropout. With Merobix that data is reachable from any browser or phone, so one operator can watch several sites at once instead of driving to each.
Merobix connects to the controllers and analyzers common on renewable natural gas (RNG) upgrading plants using its standard protocol drivers, so it can monitor the upgrading train the same way it monitors the digester. Upgrading systems that strip CO2, H2S, moisture, and other components to reach pipeline-quality methane are typically run by a PLC and instrumented with gas analyzers that speak Modbus TCP/RTU, OPC UA, EtherNet/IP, or similar protocols — all of which Merobix reads. That lets a plant trend product-gas methane purity, monitor compressor and membrane or PSA skid status, and alarm on off-spec conditions. Merobix positions this as a generic monitoring capability driven by open protocols, not a pre-built RNG package, and its engineers scope each upgrading plant to the specific equipment on site.
It depends on the site's connectivity, staffing, and data-control requirements — Merobix offers the same platform both ways. Cloud-hosted SCADA is the usual fit for distributed or unmanned digesters: it is fully managed, typically live in three to five days, requires no on-site server, and lets operators watch every site from a browser. On-premise SCADA runs on the plant's own servers or VMs, can be fully air-gapped, and keeps all data on site for operations with strict data-residency or network-isolation policies. Because it is one platform sold both ways, a biogas operator can start in the cloud and move on-premise later, or run a mix across a fleet, without changing systems.
Digester, gas-skid, H2S, CHP, flare, and RNG monitoring on one platform — cloud-hosted or fully on-premise, custom-quoted with no per-tag or per-client fees.