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Commodore PC Still Controls Heat and A/C At 19 Michigan Public Schools
jmulvey writes: Think your SCADA systems are outdated? Environmental monitoring at 19 Grand Rapids Public Schools are still controlled by a Commodore Amiga. Programmed by a High School student in the 1980s, the system has been running 24/7 for decades. A replacement has been budgeted by the school system, estimated cost: Between $1.5 and 2 million. How much is your old Commodore Amiga worth?
So less than 2 dozen schools need to spend upwards of $2 million dollars to... control the HVAC?
Really?
That is the bigger issue, IMHO...
Yeah. You could probably replace the thing with a raspberry pi .... at each location ... with a custom controller card.. and another one to control them all... for about $5,000
$2M ? Someone's pork barrel overfloweth.
I love that a 30 year old computer is doing the job just fine.
I love that a kid wrote the code ages ago, and presumably it has never even been patched.
I love that the Amiga was so damn rock solid that it has not had an emergent failure in 30 years.
I love that it uses walkie talkie beeps as a protocol
I love that somehow it is going to cost 2 million dollars to reproduce something a kid did in his spare time, presumably simply for the privilege of getting to play with a $1300 dollar computer.
And what do you do if a part dies? Where are you going to get parts for something that has not been manufactured for 20+ years?
Obviously it needs to be replaced just so you can have something that can be repaired. The $2mil probably includes upgrading a large part of the HVAC system. If you have a 20+ year old computer controlling the HVAC, then you probably have a 20+ old HVAC.
Just a Tuna in the Sea of Life
The original programmer is still around, and occasionally does some maintenance on the programmer -- he even comments extensively in the comment section for the linked news story about the specific challenges they face. (He's "Jeff").
The $2MM will be used for a general upgrade of all the heating/cooling facilities, which will include more modern control systems. Many of the systems that used to be controlled by the Amiga have already been replaced, and the Amiga doesn't manage those any more :)
I used to work for an HVAC controls company. Most controls contractors have a specialty, whether it be hospitals, schools, commercial offices, or whatever. The one I worked for specialized in schools. We would typically get the entire school district's business all at once, but individual buildings would be upgraded or added to over time. But occasionally, we would get a large project that involved multiple buildings or an entire take-over of a whole district's HVAC controls.
I have personally seen, held, and deposited a check for over $1 million from one such project. And that was the 20% kick-off payment. We outfitted 11 schools with complete direct-digital controls (none of that old pneumatic stuff), a web-facing control server, and a bunch of wire-runs to connect it all together. The price (as you may have calculated) was around $5 million. This was 10+ years ago, too.
That project covered a high school, 2 middle schools, and 8 elementary schools. The district administration offices were on the high school campus as well, and were part of the same system that covered the high school building itself.
The high school had (from memory):
- 300+ fan powered terminals (zone controller and thermostat for each)
- 7 or 8 air handling units (multi-program controller for each)
- 12 roof-top units (single-program controller for each)
- 1 network bridge
- 1 web-facing server
The middle schools had:
- 150 FPT zones (average)
- 3 or 4 AHU's each
- 6-8 RTU's each
- 1 network bridge each
The elementary schools had:
- 50 FPT zones (average)
- 1 or 2 AHU's each
- 3 or 4 RTU's each
- 1 network bridge each
All told, parts for that project cost us around $2-to-2.5 million. We generally bid things with a 100% markup over parts costs, which covered labor, design, documentation, management, and everything else. This company was and is profitable, but isn't making anyone wildly rich.
There is no pork in that barrel. It just costs money to build something like that.
When the Amiga system originally went in it was controlling well over 100 buildings throughout the district, including the entire GRCC campus at the time. The Amiga replaced the head-end of the system, which was experiencing expensive hardware failures every year ... and you couldn't get parts for that mini-computer on e-bay. It is essentially acting as a huge database (schedules, configurations, control programs, history, etc.), system manager, and monitoring system ("head-end") for the remaining 19 buildings HVAC systems. If the Amiga goes down, the buildings will continue to operate using the configurations last received, with most of the individual device controls being able to be manually overridden inside each building, albeit with less energy efficiency. What you will loose is the ability to change schedules/custom control code/configurations and the ability to centrally monitor the performance of the buildings.
Each building has one or more local control systems, and those systems communicate back to the central head-end over radio-modem (there was no district-wide network back then). Schedule and other control changes are sent to the buildings and alerts/reports are sent back. That old equipment in the buildings, even older than the Amiga, is what dictates the radio communications link. They incorporate specific protocols for keying up the radio that are not directly compatible with a newer serial to Ethernet type device that would seem like a logical replacement.
The control systems themselves gather temperatures, both inside and outside the building, look at trends and do predictive control of the equipment to accomodate scheduled use of various areas of each building. For the day, this was very advanced building control and offered significant energy savings, as well as comfort in the buildings.
Over time, as buildings have been updated, sold or replaced, the local controls withing those buildings have been replaced with newer/more modern controls that communicate with newer central control systems. Replacing these controls that are local to the buildings is what is responsible for the majority of the cost I would say.
As far as the Amiga system itself, I believe most of the components are still the original. The hard drive may have failed twice over the years, requiring a rebuild from backups. They did pick up or have donated a few Amiga systems to use as parts as needed, but the system has proven to be very resilient. Obviously, Monitors, Keyboards and Mice can only take so much use without needing to be replaced. Without this, the system likely would have become inoperable and unservicable many years ago, or been incredibly expensive to keep running.
From a technical stand point, the Amiga was selected because at the time it was the only "Personal Computer" (PC) that had a true pre-emptive multi-taskng operating system. It needed to be able to handle multiple processes simultaneously, including interfacing with the systems, maintaining settings in the database, monitoring the system as well as support for both local and remote access to the system simultaneously. Basically, its capabilities fit the need. While for nostalgia reasons I would hate to see it go, it has been 30 years and I think the system has done its job. Replacing a building's control system doesn't happen overnight, and when you are talking 19 buildings with ancient (yes I am calling myself ancient I guess) control systems, it is going to take money and time. The payback in energy savings, comfort and safe control of the buildings though I think justifies the cost.
Have a Day!
You could murder someone with a Commodore 64 after fishing it out of a swimming pool filled with beer and it would still run fine.
Yes, after you replaced the power supply.
"Yeah, you're just going to have to sit in the sweltering heat during summer school until ThunderfuckThor69 sends us the PSU we need for a 30 year old computer made by a company very few of you have ever heard of."
Yeah, that'd go over well with me as a kid. Or my parents.
Non impediti ratione cogitationus.