The Torah commands us to rest on Shabbat, along with our families, workers, and animals. There's nothing on that list about digital water meters, but the halachic issue is indeed there. And that's a big problem in the modern world: Digital meters measuring electricity, water and gas are essential to the infrastructure of smart homes and smart cities that are becoming more and more common.
And according to Erez Bar-Enosh of MTR Wireless Communications, the halachic issue of “closing a circuit” (segirat ma'agal) is one of the major reasons that digital meters are not more common in Israel. Which is a shame, because they can save money for customers and resources for utilities. But now the way is clear for the full use of digital meters, thanks to the “Sabbath observant” meters developed by MTR.
The “observant” meter was developed by MTR as part of its Smart Grid product line, which lets utility companies keep a constant, vigilant eye on its utility network. The meters can be installed on any part of the grid – including at the customer's home or office – and report real-time information about problems and usage in the entire network, alerting system operators of emergencies and major issues (via SMS and other methods), and reporting on usage in a much more thorough manner than the mechanical meters that are mostly used today.
The MTR digital meters overcome the “last mile challenge” in metering, allowing utility companies to keep a constant eye out on all meters – and enabling companies to avoid having to send out a meter reader to gage actual usage. MTR's digital meter uploads the information using a proprietary communication system to a central server (it can also store information on the meter itself for later uploading). The system also enables utility operators to upload information, like database changes, to meters.
All that innovation is great, and will fit right in with plans for smart cities that encourage conservation of resources. But, as mentioned, the halachic issue in digital meters is one reason why smart city projects are not as widespread in Israel and elsewhere.
Why? Digital systems, as mentioned, constantly update as customers use a resource. Taking water as an example, the smart meter will record, and display, changes in the amount of water used by the customer. In other words, a Sabbath observant person cannot open the water tap on Shabbat, because the information in the meter is updated, as is its display, with every drop. This is not the case with mechanical meters, which measure usage indirectly (as water flows it drives piston or disk that moves a magnet which in turn drives the register.
MTR's meter has received a "Shabbat kashrut certificate" from the Tzomet Institute, which works to develop electronic products that observant Jews can use on Shabbat. The product, called Kfir, also works indirectly, measuring changes in a magnetic field that are caused by water usage. The system (called Kfir) can store information in its memory and upload it after Shabbat. And the device's screen remains “silent” over Shabbat, without an update to the data on its screen (instead of displaying constantly updating numbers, the screen displays a “Shabbat Shalom” message!) MTR's smart grid meter technology is certainly exciting enough – but the fact that it is “Sabbath observant” as well makes it awesome!