California has spent the past decade tightening the screws on building efficiency — from Title 24 energy code updates to state and local net-zero mandates for new commercial construction. Most of that conversation focuses on insulation, glazing, and HVAC hardware. A quieter piece of the efficiency puzzle, gaining traction in Europe and increasingly discussed among US facility managers, is a simpler idea: buildings run more efficiently when they actually know how many people are inside them, in real time.
That’s the core business of Acorel, a French company that’s spent more than three decades building sensor and software systems that count and analyze how people move through physical space — and a useful case study in where “smart building” technology is headed as it matures beyond thermostats and occupancy-triggered lighting.
The efficiency case for knowing who’s actually in the room
A conventional commercial HVAC system runs on a schedule: full capacity during business hours, reduced overnight, regardless of whether a floor is packed or nearly empty. Acorel’s pitch — and that of a small but growing category of occupancy-analytics vendors — is that this is a solved problem hiding in plain sight. Sensors using infrared, LiDAR, and computer vision can measure real-time occupancy accurately enough (the company cites accuracy above 98%, independently audited) to feed that data directly into building management systems, adjusting ventilation and climate control to actual usage rather than a fixed assumption.
For California building owners already navigating Title 24’s tightening requirements, this kind of demand-responsive operation is a fairly natural next step: the compliance conversation has largely been about how efficient equipment can be; occupancy analytics shifts part of the conversation to when that equipment needs to run at all.
Beyond HVAC: retail, transit, and public safety
Acorel’s business extends well past office buildings. The company’s technology is also deployed across:
- Retail and shopping centers, where zone-level occupancy data informs staffing and layout decisions — relevant to California’s dense, competitive retail corridors from downtown San Francisco to Southern California’s mall districts.
- Public transit, where the company’s onboard sensors track boarding and alighting on buses, trams, and trains to support schedule and fleet planning — a use case with obvious relevance as California transit agencies work to rebuild post-pandemic ridership while managing tighter operating budgets.
- Airports, tracking passengers from check-in through security to boarding to flag congestion before it becomes a bottleneck — a familiar pain point for anyone who has navigated a peak-hour TSA line at LAX or SFO, even though those specific airports are not confirmed Acorel deployments.
The common thread across all of these is treating foot traffic as a measurable, actionable input rather than an afterthought — the same logic that’s driven Acorel’s three-decade specialization, dating back to a 1990 municipal transit project in Lyon, France, that redirected the company from general engineering work into dedicated people-counting technology.
Privacy: the other half of the pitch
California’s own privacy framework — the California Consumer Privacy Act (CCPA), among the strictest in the US — adds a wrinkle that occupancy-analytics vendors have had to design around from day one in Europe, where GDPR has applied similar pressure for years. Acorel’s approach is what the industry calls “privacy by design”: sensors are built to detect and count anonymously, without storing images or identifying individuals, so the compliance question becomes largely moot rather than requiring a separate data-governance layer bolted on afterward.
That’s a meaningfully different posture than the camera-based analytics systems that drew scrutiny in some California retail and transit contexts in past years over facial-recognition concerns — a distinction likely to matter more, not less, as California continues to expand its privacy statute’s reach into workplace and biometric data.
A market still finding its footing in the US
Occupancy and people-flow analytics remain a more mature market in Europe, where GDPR compliance requirements and stricter urban-transit funding pressures pushed adoption earlier. In the US, the category is younger but growing, driven by a mix of post-pandemic interest in space utilization data, rising energy costs, and a broader corporate real estate shift toward flexible, usage-based office space.
Whether European specialists like Acorel expand aggressively into the US market, or whether the space consolidates around domestic players and larger proptech platforms, the underlying trend looks durable: as building codes, transit budgets, and privacy law all tighten simultaneously, the businesses that know exactly how people move through their spaces — rather than guessing — will have a real advantage in cutting costs without cutting service.
For California, a state trying to hit ambitious efficiency and emissions targets while keeping transit systems solvent and retail corridors competitive, that’s a trend worth watching closely.
