The Difference a Tool Choice Makes

Last week, in Beyond Pixels, my first tip to developers making the move from software to hackable hardware was:

Understand the capabilities of your prospective chipset or platform, and make sure they match your project goals.

My final tip was:

Use the best remote development and debugging tools you can find when you’re ready to put your project online.

These two points came to mind this past week as I faced a moment of truth about Circopt, my own hardware project: would it really save enough energy to be worthwhile?

A Little More about Circopt

In a recirculating hot water system, a booster pump keeps water flowing through a recirculation loop, so that water is kept hot and available at every access point, eg. a faucet, dishwasher, or laundry machine.

In an efficiently configured system, the booster pump is controlled by a timer. This might run the pump in the morning before people leave the house and again in the evening before going to bed; somewhere in the range of 8 hours per day. More typically, rather than be inconvenienced by a lack of hot water during off hours, the pump is always on, running 24 hours per day.

Utilizing the properties of an insulated recirculation loop, Circopt detects demand and only runs the booster pump when hot water is being used. This means that hot water is always available and the pump is only running when necessary, all without having to learn or predict the users’s habits, as learning thermostats do. (Interested in the details? Check out the patent.)

I was sure that Circopt reduced energy usage, but not how much. If knew many hours per day a booster pump would run when controlled by Circopt, I could compare it to the typical scenarios above.

Particle and Porter Power

When I set out to prototype Circopt, I chose to build it using the Particle Platform. In addition to being able to update code on a remote device, Particle’s event publishing capabilities offer a huge benefit to people like myself, who need to measure the performance of their projects.

I coded circopt so that every time it finishes running the booster pump, it publishes an event including the number of milliseconds it ran.

While you can MacGyver a data logger with Google sheets, I used Porter’s new event recording capabilities to grab a CSV of all of my pump’s running data with a just mouse click.

Downloading filtered events in Porter

From there I was able to open the file in Excel and quickly calculate how many hours per day my booster pump was running.

The Results

The results surprised even me: my pump is only running approximately 2 hours hours and 51 minutes per day.

That means it’s using less than 50% of the energy of an efficient system an less than 15% of the energy consumed by a typical system. All without any availability interruptions.

Encouraged, I then used the power rating of my pump to calculate the number of kWh saved, multiplied that by the average price I pay per kWh, and found that Circopt is saving me between $75 and $310 per year. This doesn’t even include energy savings from reducing the use of the water heater itself, or factor in reduced wear and tear on the overall system.

The Difference

This information drastically changed my thinking of the future of Circopt’s development.

Initially, I saw the technology only as being integrated into booster pumps by one or more existing manufacturers. But, the first year savings of at least $75 beat the $59.89 (plus breadboard) I spent on the terribly uneconomical build of my prototype:

  • 1 x Particle Photon for $19.00
  • 1 x Flow meter for $14.90
  • 1 x PowerSwitch Tail for $25.99

With an even lower cost of production at scale, providing Circopt to existing recirculating hot water systems is a market too big to ignore. I now see that part of Circopt’s future includes an off-the-shelf product which can control any booster pump.

The Importance of Platform and Tools

The Particle Platform and Porter made critical data quick and easy to find. Would I have eventually arrived at the same conclusion without these tools? Possibly, but the difference comes down to timing.

This insight arrived early enough in product development to influence the plan and get Circopt into more people’s hands sooner than anticipated.

I feel sure that all of us working on products that we hope will contribute to making the world a better place want broader, faster reach. How we get there, and what gets us there, is important in achieving those goals.


While Porter is both my own project and a tool I use, I’d love to hear about your favorite platforms and tools and how they shaped your projects and thinking. I listen here; and, you can also find me on Twitter.