MeghDrishti মেঘদৃষ্টি

See the cloud before the power drops.

মেঘ আসার আগেই দেখুন, ডিজেল পোড়ানোর আগেই ভাবুন।

MeghDrishti watches the sky with a low-cost camera and tells solar operators in Bangladesh what the next two hours will bring, so they stop running diesel gensets just in case.

  • Monsoon clouds move fastA rooftop plant can lose half its output within minutes, then recover just as quickly.
  • Diesel runs just in caseWith load shedding and costly fuel imports, factories keep gensets on standby because they cannot see a drop coming.
  • Hourly forecasts can't see a cloudA sky camera can. In our research it gave the biggest gain on partly cloudy days.
Demo mode: simulated sky and power, shaped on our SKIPP'D results. Live model connects in Round 2.
CAM-01

Scanning the sky.

Rooftop fisheye camera, one image per minute. The dashed line marks a cloud on course for the sun.

09:00

Solar output, next 2 hours

Measured Forecast median 50% range 90% range Persistence Clear-sky limit

Diesel kept off today

Compared with keeping the genset on standby whenever the sky is not clear.

0litres of diesel saved
0BDT saved
0kg CO₂ avoided
0standby hours avoided
Edit assumptions

CO₂ uses 2.68 kg per litre of diesel. MeghDrishti puts the genset on standby only during red alerts.

What the model looks at

Share of attention per source as the forecast looks further ahead.

Sky images Recent power Weather forecast

Pattern from our paper (Fig. 6): the camera matters more for longer leads and on cloudy days. Weights are descriptive, not causal.

Operator alerts in Bangla

Sent by SMS or app when the advice changes.

মেঘদৃষ্টি সতর্কবার্তা

Panel cleaning advisor

On clear periods, measured output should match the physics-based clear-sky limit. A growing gap means dust on the panels.

Dust loss rate is an assumption until measured at the Dhaka pilot site.

From one sky photo to one clear instruction

Every five minutes MeghDrishti runs the same loop on a small computer at the site. It keeps working on a weak internet connection because the model is small enough to run locally.

  1. CaptureA Raspberry Pi with a fisheye lens photographs the whole sky every minute, for under BDT 15,000.
  2. CorrectTimestamps are checked against the sun's path, and pvlib computes the clear-sky limit for the site.
  3. ForecastHAMF fuses the last three sky images, 60 minutes of power and the clear-sky prior into 19 quantiles for 5 to 120 minutes ahead.
  4. DecideRules turn the forecast range into one action: charge the battery, delay a load, keep diesel off, or prepare the genset.
  5. AlertThe operator gets the action in Bangla on the dashboard and by SMS, with how confident the forecast is.

Built on tested research, with honest limits

The forecasting model comes from our research on SKIPP'D, a public dataset of sky images and PV power (517 days). The paper is under double-blind review.

Model (20 test days)RMSE (kW)Skill vs persistenceProbabilistic skill90% range width
HAMF (ours)3.3817.9%34.8%5.6 kW
TiDE-style dense model3.4715.8%31.3%6.6 kW
Probabilistic persistence4.120.1%0.0%9.8 kW
Smart persistence4.120.0%−16.6%–
SUNSET CNN (benchmark)4.25−3.1%−80.9%–

HAMF beats persistence and the SUNSET benchmark with p < 0.001. Its 90% range is 43% narrower than probabilistic persistence while covering more observations (87.6% vs 83.4%).

328,309 records in the public dataset carry a daylight-saving timestamp error that we found. Left uncorrected, it inflates skill by about 7 points. MeghDrishti checks every site's clock against the sun before training.

What we still need to prove

  • The model was trained at one site in California. Performance in Bangladesh is untested until our Dhaka camera pilot.
  • The gain over a strong dense baseline (TiDE-style) is not statistically significant (p = 0.20).
  • Packaged weather forecasts added no skill at these horizons. The camera does the heavy lifting.
  • Diesel and CO₂ numbers in this demo come from the stated assumptions, not field measurements.

Plan through the Grand Finale

Each round moves one step from research result to a working system on a Bangladeshi rooftop.

  1. Idea and evidenceProposal, research results and this interactive prototype.
  2. Live demo at AIUBForecasts from real Dhaka sky images and a first local comparison against persistence.
  3. PilotFine-tune on local data, SMS gateway, satellite fallback for sites without a camera, and trials with one factory and one mini-grid.