Bridging Smart Grid and Smart Homes

The Potential of Home Metering

Posted by dave on October 24, 2023

As the evolution of smart grid technology moves forward, smart home metering emerges as a pivotal link for enhanced energy management. This article explores the potential of smart home metering in harmonizing energy flow between homes and the grid, delving into the challenges faced and envisioning a path towards a more integrated and efficient energy ecosystem. Smart home metering can play a significant role in advancing a sustainable energy future.

A Tale of Two Smart Worlds

In one smart world lies the evolving electrical grid. A huge labyrinth of wires and machines that power our lives. In the other world are our smart homes. Our little fortresses of solitude that provide shelter and comfort.

These worlds are connected by what is called a "revenue meter", mounted outside the house, that measures the home's electricity usage every fifteen-minutes, or so, and reports back to the local electric utility. Every month, like clockwork, a bill arrives in the mail showing how much electricity was used and how much is owed. The more things change, the more they stay the same.

Moving to a renewable grid will surely be a bumpy ride as fossil generation gives way for more variable renewable generation. The ability to alter load during times of grid stress, when either too little, or too much, renewable generation is available, will play an ever more important role in maintaining grid reliability and economics.

Homes make up a very significant portion of our electrical grid. Specifically, in 2022, residential electricity retail sales constituted almost 40% of total electricity retail sales in the country (1). Sadly, they are a "forgotten" grid resource capable of providing significant flexibility alongside their larger siblings, the industrial and commercial customers. They may be smaller in size but are larger in number.

A major issue is that homes are economically disadvantaged when it comes to participating in flexible load programs such as demand response.
The cost of industrial and commercial products, in most cases, is too high for homes because they are typically produced in low volumes and driven by specific, formal industry requirements and regulation.

Distribution grid networks, including advanced metering networks, are typically secure proprietary systems that are designed for critical internal operations, and closed to the outside world. In addition, most grid metering networks were designed to collect meter interval data for billing purposes, not to collect very large volumes of real-time power and energy data for operations. These meters are really cash registers at the end of the last mile.

The result? Grid metering technology changes slowly over time, and is expensive.

Technology in the home is driven by an entirely different set of requirements. Enjoyment and convenience nudged by social media trends. The faster, the better! The higher the resolution, the higher the bandwidth, the faster the response, the better. The sooner, the better. The more compatibility, the better. With large volumes all the while helping to drive down costs.

Fast home networks are very affordable. They use secure, high performance, off-the-shelf technology that provides a lot of "bang for the buck". This networking is designed for high definition video streaming, CD quality audio and low latency real-time multiplayer gaming, all from the comfort of a couch. Smart devices of all shapes and sizes hang off the home network.

Why not enable these ubiquitous resources by allowing a set of readily-available and inexpensive current transformer (CT) home electrical power monitoring devices to source meter data that is of sufficient quality and accuracy for aggregating into grid markets. This would open up a large latent resource of smart homes that could participate cost-effectively in grid flexibility and demand response programs.

A Path Forward

Utilities will continue to evolve their distribution field networks and smart meters. This will be a slow process and will take time. Time we really don't have.

A nearer-term solution would enable off-the-shelf, commodity home power meters to serve as bridges from the past to the future.

A path forward is to specify a low cost-of-entry process for approved whole-house energy monitoring devices that are compatible with open home device network standards (ZigBee, Z-Wave, Matter) and meet the accuracy required by grid operators. At a minimum, this could be as simple as a list of specifications and acceptable devices available on the web. Importantantly, home meter data could be checked against the utilities revenue meter data as needed.

The smart home power data could be stored in a secure cloud, while maintaining privacy, and made available as needed for energy programs using a documented and preferably open, secure application programming interface. Commodity power meters would enable a plethora of innovative systems and solutions. This would help fuel a growing energy-aware ecosystem.

We need to supplement the utility-centric metering solution with a home-centric metering solution that leverages rapidly emerging smart homes to significantly reduce costs. This would enable homes to engage with the energy system as active participants helping move us toward a renewable future.

(1) https://www.eia.gov/energyexplained/electricity/use-of-electricity.php#:~:text=The%20industrial%20sector%27s%20percentage%20share,industrial%201.01%20trillion