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TDSBot for solar panel cleaning water quality
Real-Time RO Monitoring for Solar Panel Washing
TDSBot installs on the RO output feeding your cleaning equipment and measures TDS, reject ratio and flow every minute — so every clean is verified in spec before it starts, and logged with a timestamp after.
RO + DI output monitorUpdated every hour
Tap a tab above to see readings change
4.2ppm
RO permeate TDS · current reading
Spot-free · within spec
RO outlet4.2 ppm
Alert level10 ppm
Reject ratio97.3%
RO membrane performing normally. Output 4.2 ppm — safe to clean. Panels will dry residue-free.
For Farm Operators
A bad clean costs you output for months, not days.
Out-of-spec water leaves mineral deposits on the panel surface that physically block sunlight — and they sit there until the next scheduled clean, often months away. TDSBot monitors the cleaning contractor's RO output and gives you a timestamped record that every clean actually used water that cleans.
<10
ppm TDS to clean without residue — no exceptions
3–8%
Output loss from mineral deposits after a bad clean
For Cleaning Contractors
Stop guessing when the RO failed. The data has a timestamp.
When a farm owner asks whether a clean actually met spec, "I think so" is not an answer. TDSBot logs every minute of RO output — TDS, reject ratio, flow rate — so you can show exactly what the water quality was at the moment of every cleaning event, not just claim it.
1 min
Measurement interval — hourly or daily upload
97%+
Reject ratio tracked — membrane health visible
For Mobile Fleets
12 trailer units deployed today. Was the water in spec at every farm?
One degraded membrane on one trailer unit means every farm on that route gets cleaned with water that leaves deposits instead of removing them — and nobody finds out until a client complains weeks later. TDSBot monitors every mobile unit’s RO output and logs a record for every site, every visit.
All units
Fleet dashboard — every trailer, one view
0
Sites cleaned blind when every unit is monitored
The science of pure water cleaning
Why TDS below 10 ppm.
No exceptions.
Pure water evaporates with nothing left behind. Above 10 ppm, dissolved minerals crystallise on the surface — that's the spot. Two-stage treatment: RO membrane (95–98% rejection) + DI resin polishes to near-zero TDS. TDSBot monitors both stages.
At 35 ppm
35ppm
Ca²⁺, Mg²⁺ and Na⁺ present in solution. When water evaporates, mineral ions crystallise on the surface — white deposits are visible to the naked eye at 20 ppm and above.
On the panel
Mineral deposits form as water evaporates — physically blocking sunlight until the next scheduled clean.
At 4 ppm
4ppm
Virtually no ions present. Water is chemically attracted to mineral deposits on the surface — it actively cleans. When it evaporates, nothing is left behind.
On the panel
No residue. Full sunlight reaches every cell. No output loss until the next scheduled clean.
RO rejection required (95–98%) → DI polish to <1 ppmTwo-stage
One threshold. Months of consequence.
A cleaning failure leaves deposits
that cut output for months.
Out-of-spec water leaves mineral deposits that cut panel output 3–8% — and stay until the next scheduled clean, months later. TDSBot ensures every clean uses water that actually cleans.
3–8%
Output loss from mineral deposits after bad clean
6 mo
Until next cleaning cycle fixes the problem
Mobile RO unit monitoring — verify water quality before each cleaning event
Cleaning log — timestamped raw TDS readings per cleaning event, always exportable
Remote site alert — email notification if water quality drops mid-clean
Solar farm log — continuous TDS record; whether it supports a specific warranty claim is a question for your panel manufacturer
Also cleaning with pure water?
Same <10 ppm threshold, different operational stakes — dedicated pages for car wash tunnels and window cleaning depots.
What a bad clean costs
One bad clean. Months of lost output.
A degraded membrane doesn't just risk one bad clean — because solar farms are only cleaned periodically, deposits from a bad clean sit there reducing output until the next scheduled clean removes them, often months later.
It gets worse if it happens more than once. Repeated cleaning with out-of-spec water lets those mineral deposits harden into scale a normal wash won't remove — at that point you're looking at a descaling job.
Example · 500kW array · 5% loss · 90 days · $0.12/kWh
$1,080 lost generation
Plus contractor liability if the farm owner traces the cause
If it repeats · deposits harden into scale
Descaling, not just a clean
Acid treatment or specialized removal — costs more, takes longer, and the array stays underperforming until it’s done
With TDSBot · verified in-spec before cleaning
$0 lost generation
Clean deferred until membrane serviced. Panels cleaned right the first time.
Without TDSBotSilent failure
Day 0Mobile unit arrives at farm. RO output 22 ppm — membrane at 89% rejection. Nobody checks.
Day 0Panels cleaned with out-of-spec water. Deposits begin forming as the water evaporates.
Day 0+Farm generates at reduced output. Looks like normal weather variance — nobody notices.
Day 45Owner's monitoring software flags underperformance vs. expected yield. Cause unclear.
Day 90Next scheduled clean removes deposits. Output recovers — 90 days after the fact.
90 days reduced output$1,080+ in lost generation
With TDSBotCaught early
07:40TDSBot detects RO output rising overnight — reject ratio down to 91%.
07:50Outlet TDS at 10 ppm, approaching threshold. App alert sent before the crew arrives.
08:00Contractor checks the app before starting. Confirms 11 ppm on-site — above spec.
08:10Cleaning deferred. Backup DI cartridge swapped on-site. Output verified at 3 ppm.
08:30Cleaning proceeds with in-spec water. Timestamped log recorded for the client.
0 days reduced output30min delay · $0 lost generation
How TDSBot installs
Two configurations, mobile or fixed
Mobile / trailer RO
Solar farm and large-scale mobile cleaning
TDSBot installs on the outlet of a trailer-mounted or vehicle-mounted RO unit. Before cleaning begins, the operator checks TDS output from the mobile app. If water is in spec, cleaning proceeds and the timestamped TDS reading is logged. If TDS is out of spec, cleaning is deferred until the membrane is serviced.
S1: Mobile RO unit permeate outletConnectivity: 4G LTE with hotspot cellular gateway if no site WiFiLog: Timestamped clean record per dateAlert: Email if quality drops during clean
Fixed on-site installation
Utility-scale farms with dedicated on-site RO
Larger farms with permanent RO infrastructure on-site get TDSBot installed inline on the permeate line, monitoring continuously between cleaning cycles rather than being checked once at each visit. Second sensor option on the feed inlet for dual-sensor reject ratio tracking.
S1: Post-RO outlet · alert at >10 ppmS2 (optional): Feed inlet · full reject ratioMonitoring: Continuous, 24/7Install: 1/4″ quick-connect fitting · 20 minutes
Membrane health over time
Degradation is gradual. Failure is sudden.
At 97% rejection: 6 ppm — spot-free. At 85%: 30 ppm — complaints. DI resin exhausts separately. Neither failure is visible to the eye.
TDSBot sees the trend crossing 10 ppm weeks before a complaint. Planned service, not a Saturday emergency call-out.
6 ppm
Outlet TDS at 97% rejection (new membrane)
30 ppm
Outlet TDS at 85% rejection (degraded — spotting occurs)
TDSBot detects the rejection trend falling weeks before it crosses the 10 ppm threshold
Schedule a planned membrane service instead of an emergency Saturday call-out
Dual-sensor reject ratio distinguishes membrane degradation from bypass valve drift or feed pressure drop
RO outlet TDS · 16-week trend
W1–W10: 3–7 ppm — membrane healthy, spot-free output
W11: TDS rising — rejection falling below 94%. TDSBot tracking trend.
W12: TDSBot alert fires at 10 ppm. Service booked. Cleaning continues on backup RO.
W15 (without TDSBot): 32 ppm — first customer complaint. Emergency call-out.
Pricing
Hardware + software.
One straightforward price.
Buy the sensor once. Plans are chosen in the app after your TDSBot arrives — upgrade, downgrade or switch anytime, no lock-in.
TDSBotStandard
$59one-time
Hardware · one-time
No display — readings via app & dashboard1/4″ inline flow meter2× conductivity + temperature probesWiFi + Bluetooth (BLE)Micro-USB poweredIndoor use · quick-connect fittings
Order TDSBot
TDSBot DisplayWith display
$69one-time
Hardware · one-time
LCD display — live TDS visible at the unit1/4″ inline flow meter2× conductivity + temperature probesWiFi + Bluetooth (BLE)Micro-USB poweredIndoor use · quick-connect fittings
Order TDSBot DisplayBigger lines
3/8″ · 1/2″ · 3/4″ · 1″
Larger flow meter sizes available for commercial tunnel washes, industrial RO systems and high-flow installations.
Data plans
What the sensor sends,
and how often
All three plans measure every minute — what changes is how often data leaves the sensor, and which analysis runs on it.
Monitor
$2/device/mo
Billed monthly or annually (−15%)
Every minuteDaily uploadEmail alerts
TDS, Temperature, Flow — every minute
Threshold alerts when exceed your set levels
Predictive filter depletion (configurable, default 30 days)
Daily pass/fail status report
Multi-site fleet dashboard — corporate → store hierarchy
Full log per filter cycle — resets when filter/RO membrane is changed
ESG report
Protect
$3/device/mo
Billed monthly or annually (−15%)
Every minuteHourly uploadEmail alerts
Everything in Monitor +
Hourly upload
Data-driven filter change scheduling
LSI + Larson-Skold @25°C, 93°C and 130°C
Estimated hardness + cumulative hardness load
Full log per filter cycle — resets when filter/RO membrane is changed
Pro
$7/device/mo
Billed monthly or annually (−15%)
Every minuteHourly uploadEmail · WhatsApp soon
Everything in Protect
Multi-site fleet dashboard with LSI / LS view
Corporate → site hierarchy — ops team sees all, baristas see theirs
Monthly ESG water report — liters filtered, cartridges saved
Full log per filter cycle — resets when filter/RO membrane is changed
Everything included — no add-ons, no per-feature upsells.
Estimate your ROI · adjust to your farm, all figures USD
$1,530
Total cost of one bad clean — lost generation + emergency service call
$3,500
Descaling, only if a bad clean repeats and deposits harden
$36
TDSBot monitoring cost per year, per device
Adjust the numbers above to your own array — size, output, and days between cleaning cycles all vary a lot by farm and contract. Descaling only applies if a bad clean repeats and deposits harden into scale; it's shown as a separate line since it's a compounding risk, not a cost of a single incident.
Solar panel cleaning is high-stakes — a bad clean leaves deposits that sit there for 6 months until the next scheduled clean and cost the farm owner in lost generation. We now run TDSBot on every trailer RO unit and provide the client a timestamped water quality log for each cleaning event. It's become part of our service contract.
Common questions
Before you install,
the straight answers
Solar panel cleaning requires water below 10–20 ppm TDS to avoid leaving mineral deposits that reduce panel output. Pure water evaporates cleanly, leaving nothing behind. Water above 10–15 ppm leaves dissolved calcium, magnesium and other minerals on the panel surface as it evaporates — these deposits are not just cosmetic, they physically block sunlight from reaching the cells, cutting output until the next scheduled clean removes them, which can be months away.
Yes. TDSBot installs on the RO output at the cleaning equipment or mobile trailer unit. If water quality falls outside spec, TDSBot alerts before cleaning begins — preventing mineral deposits that would otherwise reduce panel efficiency for months until the next cleaning cycle. For solar farm operators and cleaning contractors managing large arrays, TDSBot provides a continuous, timestamped record showing that cleaning water met specification on each cleaning date.
TDSBot requires connectivity to upload data and send alerts. In locations without WiFi, a 4G LTE mobile hotspot or a dedicated SIM-equipped gateway device can provide connectivity. For remote solar farm sites where connectivity is intermittent, TDSBot can store readings locally and upload in batches when connectivity is available — alerts fire when the device comes back online. For sites where any connectivity is impractical, TDSBot can be configured in local-only mode with a direct Bluetooth connection to a tablet for on-site monitoring. Contact the team to discuss connectivity requirements for your specific deployment.
TDSBot provides a raw, timestamped sensor record of water quality at each cleaning event — this is verifiable data, always exportable. Whether that record satisfies a specific manufacturer's warranty or maintenance documentation requirement is a question for the panel manufacturer or the warranty terms in question; TDSBot does not make compliance claims on your behalf. Many operators find the log useful as supporting evidence and as part of a service contract with the farm owner, independent of any specific warranty determination.
With a single outlet sensor, it can't — both membrane degradation and insufficient feed pressure increase outlet TDS. With dual sensors (feed inlet and permeate outlet), TDSBot calculates the reject ratio. If reject ratio falls, the membrane is degrading. If reject ratio holds but outlet TDS rises because inlet TDS has risen, the membrane is fine but the source water is harder. Dual sensor is recommended for any mobile unit where diagnosing the cause matters, not just detecting the symptom.
TDSBot uses quick-connect fittings that work with 1/4″ to 1 1/2″ water lines. TDSBot is built for indoor/enclosed mounting — on a trailer or vehicle-mounted unit, install it inside the equipment housing or a protected cabinet, not directly exposed to spray or weather. Installation takes about 15 minutes. The device connects via 4G LTE where site WiFi isn't available, and runs independently between sites. Before cleaning begins at each site, the operator checks TDS output from the mobile app — if water is in spec, cleaning proceeds and the reading is logged automatically.
Don't wait for the next inspection to discover a bad cleanKnow your water is in spec
Know your water is in spec
before every clean, every farm
TDSBot installs in 20 minutes. Alerts within minutes of a threshold breach. The cost of one prevented silent RO failure pays for decades of monitoring.
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Disclaimers: TDSBot measures TDS, conductivity, temperature and flow rate directly. LSI, Larson-Skold Index, hardness and alkalinity estimates are derived from onboarded utility water chemistry data — not directly measured inline. TDSBot does not measure PFAS, bacteria, or other biological or chemical contaminants; for RO systems, reject ratio is used as a proxy indicator of membrane performance only. TDSBot monitoring data is not a substitute for accredited laboratory testing or statutory water quality compliance testing. All third-party brand names are trademarks of their respective owners; WaterTDS Inc. claims no affiliation, endorsement or partnership unless separately announced.
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TDSBot® · PWSID cross-referenced · EPA SDWIS · SCA Water Standards