Engineering, tested and explained.
A calibrated meter, a 3 kW immersion heater and a popular solar diverter were left to argue for four weeks. The app's self-consumption figure was tidy; the airing cupboard told a more complicated story about standing losses, legionella cycles and what a 4 kWp array can actually displace.
A 30 mA RCD that trips on an October evening is rarely reporting a single fault — it is reporting a sum. This is an account of four weeks with a leakage clamp meter in an 1898 terrace, measuring nine circuits one at a time to work out where the milliamps actually go, and which of them represent a genuine deterioration rather than the ordinary arithmetic of modern appliances.
Powerline adapters are often sold as a way to avoid pulling cable through an old house. In a Victorian terrace, the mains is a shared, noisy and topologically awkward medium. A month of measurements across three circuits shows where throughput survives, where latency collapses, and why the ring final is not a network.
A forty-day doorstep audit of three video doorbells, instrumented to separate button-press latency from motion wake-up cost and cloud dependence. The useful question is not how good the picture looks, but what happens in the seconds before the notification arrives — and what remains when the broadband does not.
A calibrated mains-frequency logger spent twelve months plugged into a British ring main, counting cycles and recording the grid's smallest deviations. The result is a portrait of a system that is tightly controlled, quietly active and more variable in its physics than its headlines suggest.
CavLab ran three sub-£100 NDIR carbon dioxide monitors alongside a calibrated reference for the first nine weeks of a British autumn term. The displays agreed with each other far more readily than they agreed with the reference, and the errors were not random — they drifted in a direction that makes a stuffy room look acceptable.
Onboard 230 V sockets are not a small version of the mains at home. Over a series of UK journeys in autumn 2026, we logged voltage sag, waveform distortion and dropouts at the seat, then watched how USB-C chargers and laptops reacted. The results separate cosmetic annoyances from genuine electrical risks — and show where railway engineering is simply doing its job.
Five outdoor smart sensors, one British winter and a set of IP ratings that promised more than they could deliver. We compare claimed ingress protection with condensation, cold batteries and the realities of a wet garden.
A 7.4 kW charger is a 32 A load that runs for hours, not minutes. We instrumented one on an older consumer unit to see where thermal behaviour, voltage drop and diversity diverge from the installation paperwork.
Plug-in solar kits are being discussed as a simple route to domestic generation, but a British winter is a stern test. We instrumented an 800 W balcony kit for six months, logging yield, inverter behaviour and the arithmetic behind payback.
Smart thermostats and hubs promise convenience, but their network behaviour is rarely examined. Using a mirrored WAN port and local DNS logging, we mapped a week of traffic from common UK smart-home devices and tested how much control survives without the cloud.
Eight soil-moisture nodes, one solar-powered gateway and a Grafana dashboard, run across the 2026 growing season on a UK allotment site. Here is what the radio link, the batteries, the enclosures and the data actually did when the weather stopped cooperating.
Four connected kettles, one dumb control and a calibrated power analyser: we measured real energy-to-boil, idle radio draw, keep-warm costs and whether a 70 °C setting actually reaches 70 °C. Some features earn their Wi-Fi. Most do not.
A 900 Mbps full-fibre service was instrumented for 30 days to separate access-line performance from Wi-Fi and home-network effects. Wired throughput held close to the advertised median at peak, but latency and the tenth percentile told a more honest evening story.
A SMETS2 electricity meter, its in-home display and a calibrated energy logger were logged side by side for 30 days. Daily totals agreed closely, but tariff boundaries and display rounding showed where a time-of-use household can misread its own data.
A week with plug-in monitors and a whole-house logger in a Sheffield semi quantifies what stays awake when the house is quiet. The always-on floor is larger than most smart-home advice assumes, and much of it cannot sensibly be switched off at all.
CavLab put four UK-market e-bike packs through a controlled discharge and charger test regime, then rode a fixed Pennine loop to see how bench watt-hours translate into real miles. The gap between nameplate capacity, usable energy and advertised range turns out to be engineering, not marketing alone.
The UK three-pin plug is heavier, bulkier and more expensive than almost any rival — and it is still the safest domestic mains connector in common use. We dismantled one, traced the design decisions behind BS 1363, and asked whether a standard written for post-war copper shortages still fits a home full of EV chargers and heat pumps.
Solid walls, suspended timber floors and a bay window: the pre-1919 terrace is the hardest test in British retrofit. We built an instrumented rig to model one, ran it across a range of flow temperatures, and compared the measured results with the figures printed in manufacturer literature.