Introducing WHIP: Energy Management Done Right
Part 4 of the Smart Home Energy Management series. ← Previous: What Energy Management Actually Requires
Why WHIP?
After years of building PV/battery systems and wrestling with existing smart home platforms, we decided to build what we actually needed: an energy management system designed from the ground up for the task.
WHIP is our answer to the requirements outlined in the previous article. It's a full-stack smart home framework—and energy management is one of its core strengths. What sets WHIP apart is its hardware foundation: a robust, wired infrastructure designed for reliability and longevity.
WHIP stands for Witty House Infrastructure Processor. Yes, the name is tongue-in-cheek.
Design Philosophy
Energy-First, Not Device-First
Traditional smart home platforms model the world as a collection of devices. WHIP models the world as energy flows between sources, storage, loads, and the grid. Devices are just the mechanisms through which energy moves.
Optimize, Don't Just Automate
Rule-based automation ("if solar > 2kW, start dishwasher") is brittle and suboptimal. WHIP uses optimization algorithms to find the best decisions given forecasts, constraints, and user priorities.
Local-First, Cloud-Optional
Core functionality runs on-site. Cloud services enhance capabilities (weather data, remote access) but aren't required for the system to function.
Architecture Overview
WHIP consists of three abstraction layers, each capable of operating independently:
Hardware Foundation
- Nodes: STM32-based microcontrollers running FreeRTOS, connected via 1MBit CAN bus. Each node handles sensors, actuators, and local logic. Nodes can operate independently—no higher-level system required for basic functionality.
- Hubs: Raspberry Pi-based aggregators that monitor CAN networks, provide Ethernet gateway services, handle firmware updates, and bridge to higher-level systems.
- Server: Linux-based control layer providing visualization, internet connectivity, third-party integrations (ZoneMinder, Kodi, weather services), and cross-system coordination.
- Software Layer: On top of this hardware runs the energy management logic described in the features below.
Why CAN Bus?
The CAN bus backbone provides robust, interference-resistant communication at 1MBit. No WiFi dropouts, no cloud dependencies, no single point of failure. Each node is a self-contained unit that continues operating even if the network is disrupted.
Key Features
Intelligent Battery Management
- Forecast-aware charging: Don't fill the battery if tomorrow is sunny
- Grid tariff optimization: Charge during cheap hours, discharge during expensive ones
- Longevity protection: Avoid unnecessary cycles, respect temperature limits
Load Orchestration
- Automatic load shifting to solar surplus periods
- Priority-based shedding during supply constraints
- EV charging optimization with departure time awareness
Grid Interaction
- Dynamic export limiting
- Peak shaving for demand charge reduction
- Feed-in tariff optimization
Resilience Features
- Automatic generator start on grid failure + low battery
- Island mode coordination
- Emergency reserve management
What's Next
This article introduces WHIP conceptually. In upcoming articles, we'll dive deeper into:
- Installation and Setup: Getting WHIP running on your system
- Configuration: Defining your installation, constraints, and objectives
- Integrations: Connecting specific hardware (Victron, Fronius, etc.)
- Advanced Topics: Custom optimization objectives, multi-site coordination, API usage
WHIP is the culmination of what we've learned from years of hands-on experience with energy systems. It's opinionated software—built by competent practitioners, for bold practitioners.
Is WHIP for you? If you are building or significantly renovating a house, prefer wired reliability over wireless convenience, and are technically inclined—yes. If you want plug-and-play or quick wireless retrofit—probably not. WHIP demands planning and involvement upfront, but delivers a system that just works afterward.