C-DRONE GUIDE · 1 AUGUST 2026
Steam-network and pipe-insulation thermography by drone: energy losses in plants, price
In a plant raising steam, every metre of degraded lagging and every valve left bare dissipates energy paid at gas prices. Those losses are invisible, scattered along kilometres of piping, and concentrated exactly where nobody goes: overhead racks, roof penetrations, inter-building gantries. A thermal camera on a drone runs along these networks in a few hours and turns diffuse losses into a costed list of points to fix — often one of industry's shortest-payback energy audits. Here is what the flight reveals, how results are ranked, and prices observed in 2026.
Published on 1 August 2026, reviewed on 21 August 2026 — regulations in force as of August 2026.
Where the heat goes: lagging, singular points, steam traps
Three deposits dominate. Degraded lagging first: slumped mattresses, torn jacketing, sections soaked by a nearby leak — wet lagging barely insulates any more, and it shows from afar in thermography. Singular points next: valves, flanges, expansion joints and supports left bare after maintenance, each radiating like several metres of uninsulated pipe — the classic target of removable insulation jackets and of the support schemes (energy-saving certificates) that fund them. Finally the steam traps: a trap stuck open passes live steam into the condensate line — its downstream thermal signature gives it away.
Infrared thermography is the reference tool of this condition-based maintenance: the review by Bagavathiappan, Lahiri, Saravanan, Philip and Jayakumar published in 2013 in Infrared Physics & Technology surveys its validated applications, from fluid networks to electrical gear, and stresses that it is non-intrusive — measurement happens with the plant running (see the study on Google Scholar). The drone adds only one thing, but a decisive one: access to elevated sections without scaffolding or shutdown.
Why the drone, specifically, on these networks
A thermographer on foot covers what he sees from the ground: the lower half of the networks. Yet racks run at 6, 10, 15 metres, cross internal roads, skirt roofs. The drone tracks the network at constant distance, on both sides, photographing every section in visible and thermal; hot spots are then located on the network drawing, with apparent temperature and a severity class. The flight happens with the plant running — that is in fact the condition of the measurement — in coordination with the site's HSE team: prevention plan, ATEX zones excluded or overflown at the prescribed distances, slots compatible with operations.
The useful deliverable ranks: a few dozen points sorted by estimated loss, from the leaking trap that pays back in weeks to the lagging section to redo at the next shutdown. This thermal-round logic extends naturally to the site's other networks — buried heat networks, substations and switchboards — pooling the mobilisation into a single day.
Reading the results: from image to action plan
A thermal image of piping is read with method. The emissivity of new aluminium jacketing is very low: it reflects the sky and can look cold while the lagging beneath is ruined — the thermographer cross-checks viewing angle, reference temperatures and visible condition to avoid false conclusions. Wind and rain cool surfaces and flatten contrasts: fly in calm, dry weather, ideally early morning. And a loss is costed in power, not degrees: the report converts measured differentials into an estimated loss per metre or per point, the only serious basis for prioritising.
That costing feeds the site's energy-efficiency workstreams — performance plans, regulatory audits, energy-saving-certificate files for insulating singular points — and is usefully repeated after works to validate the gain. On commercial sites under reduction targets, the same thermal mechanics applies to the envelope: that is the subject of our tertiary decree and drone thermography guide.
Prices observed in 2026
Ranges observed in 2026 (excl. VAT):
- Thermal round of an ordinary site's steam network (up to 2 km of piping, ranked report): €900 to €1,800.
- Large multi-network site (steam, condensate, superheated water, several buildings): €1,800 to €4,000.
- Post-works re-check (same sections, gain validation): €500 to €1,000.
- Bundling with the site's other thermal inspections (roofs, HV substations, flare): pooled mobilisation, on quotation.
Flying on an industrial site requires genuine HSE preparation (prevention plan, ATEX zoning): it is included in the service. Our thermal imaging drone page presents this family of services; request a quote stating the approximate pipe length, the fluids and the site's access constraints.
Frequently asked questions
Must the plant be shut down for the thermography?
No — quite the opposite: the measurement only makes sense with the plant under load and the networks at temperature. The flight is coordinated with operations (slots, excluded zones) but does not interrupt them. It is one of the few energy audits that costs nothing in production.
Does the drone also detect the steam leaks themselves?
A frank leak often shows (plume, localised hot spot), but thermography primarily targets insulation losses and steam traps. For combustible-gas or methane leaks, dedicated sensors exist: see our guide on gas-leak detection by drone.
Put it into practice
- Drone aerial thermal imaging: rates and cities covered from €500
- Aerial thermal imaging in Auxerre Bourgogne-Franche-Comté
- Aerial thermal imaging in Paris Île-de-France
- Aerial thermal imaging in Strasbourg Grand Est