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ops/engagementsELVY

ELVY ENERGY

Residential Virtual Power Plant

Elvy engaged us against a hard deadline: a residential Virtual Power Plant, from zero to working, inside one month — with a bonus attached to speed. A small team of Martian engineers delivered the working system in 27 days. Elvy's own engineers have been building on top of it in production ever since.

The VPP aggregates Ferroamp home-battery systems across customer households and dispatches them against the Nordic flexibility market via Flower — real batteries, in real homes, traded against a live market where a wrong command costs money. We built the service end to end: an MQTT bridge that ingests and normalizes household telemetry into BigQuery; a control plane that executes battery commands — charge plans, scheduled discharge, state-of-charge limits, power derates — with full startup recovery; and authenticated inspector APIs with an operator TUI for facility discovery, snapshots, replay, and manual control.

On top of that runtime we built the trading console Elvy's operators run the fleet from: a web dashboard for authoring and reviewing charge plans by bidding zone, drilling into any facility's Flower controls, battery topology, and state-of-charge limits, and intervening on a single site or the whole portfolio.

Because the system commands hardware in people's homes, we engineered the rollout around safety. Dry-run and read-only egress modes record and preview every command the system would have sent — against live telemetry — so operators could watch its would-be behavior before a single real command left the building. A deterministic local simulator of the entire fleet — scripted Ferroamp telemetry, scripted Flower dispatch — made the whole VPP testable on a laptop, with no hardware and no market connection.

Today it runs live: the read-only rollout has graduated to active dispatch, and the system now controls a production fleet many times the size of the pilot we handed off — real Flower commands to real homes, around the clock.

Start
Mar 2026
Duration
27 days
Stack
Python · FastAPI · Next.js · React · MQTT · BigQuery · Google Cloud · Terraform · Docker
Links

ELVY ENERGY

Residential Virtual Power Plant

Elvy engaged us against a hard deadline: a residential Virtual Power Plant, from zero to working, inside one month — with a bonus attached to speed. A small team of Martian engineers delivered the working system in 27 days. Elvy's own engineers have been building on top of it in production ever since.

The VPP aggregates Ferroamp home-battery systems across customer households and dispatches them against the Nordic flexibility market via Flower — real batteries, in real homes, traded against a live market where a wrong command costs money. We built the service end to end: an MQTT bridge that ingests and normalizes household telemetry into BigQuery; a control plane that executes battery commands — charge plans, scheduled discharge, state-of-charge limits, power derates — with full startup recovery; and authenticated inspector APIs with an operator TUI for facility discovery, snapshots, replay, and manual control.

On top of that runtime we built the trading console Elvy's operators run the fleet from: a web dashboard for authoring and reviewing charge plans by bidding zone, drilling into any facility's Flower controls, battery topology, and state-of-charge limits, and intervening on a single site or the whole portfolio.

Because the system commands hardware in people's homes, we engineered the rollout around safety. Dry-run and read-only egress modes record and preview every command the system would have sent — against live telemetry — so operators could watch its would-be behavior before a single real command left the building. A deterministic local simulator of the entire fleet — scripted Ferroamp telemetry, scripted Flower dispatch — made the whole VPP testable on a laptop, with no hardware and no market connection.

Today it runs live: the read-only rollout has graduated to active dispatch, and the system now controls a production fleet many times the size of the pilot we handed off — real Flower commands to real homes, around the clock.

Start
Mar 2026
Duration
27 days
Stack
Python · FastAPI · Next.js · React · MQTT · BigQuery · Google Cloud · Terraform · Docker
Links