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Brewery Upgrade: Heating 8,000 gallons a day on Solar?

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DIYTransit

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I'm sure the shear volume of water required got some clicks!

I have been very happily running a ~1000W solar system on my Ford Transit for a few years. I don't own a home, so my list of solar 'projects' are relatively limited. However, I do own part of a large brewery, which uses a tunnel pasteurizer to process its beverages. Effectively, this is a very long sealed tunnel that heated water is pulled from basins, and recirculated over the canned beverages passing down a long conveyor. The cans are heated from cold (34F) to very hot (160F) for the purpose of killing any bacteria in the liquid or package. The primary heating function is a boiler fed by natural gas, but our usage is astronomical.

I'm curious as to the feasibility of installing solar (significant or insignificant amounts) as a way to supplement our boiler/natural gas use. The tunnel pasteurizer gets run all day, every day, through primarily solar generating hours (6AM - 7PM). Any heat that can be added to the system would be a benefit to our overall energy use and costs, and I do not expect to size the system to replace the boiler.

The advantage of this system is that it is relatively simple to install (power is in direct current, with no inverters or battery), with very little risk in undersizing. If it is cloudy one day, or we have lower output in the winter, it is all irrelevant as we still have the boiler to make up our heat needs.

I'm just starting here as a litmus test - is this even worth exploring, or a waste of time and money?

Thanks!
 
That would require a LOT of solar panels. And yes you’ll still likely need a battery, but not a massive one (relatively). The upfront cost would likely make your knees buckle. And then, where are you going to put all those panels?
 
yodamota said:
what about offering unpasteurized beer hahahahah!
Click to expand...

This is actually a thing. Beer never used to be pasteurized. But pasteurization does eliminate exploding bottles lol. You can still find unpasteurized beer but it’s a niche thing.
 
Thanks for the responses so far. Yes, obviously this would be a huge investment. But also consider it is supplemental, so any panels would 'help' assuming the cost/benefit equation made sense.

On where the panels go - we have a ~30,000sqft roof that is in full sun 100% of the day. There are no obstructions.

On the battery side - I am not sure why it would be required, unless we have a voltage mis-match that needs to be handled. The water, of course, is the battery - and if the usage is effectively 100% of solar time, there is no need for energy storage.

Energy usage for natural gas is represented in CCF - we use approximately 3500CCF per month. An online calculator tells me that is approximately 357,000,057 BTUs.
 
Heating 8000 gallons of water from earth temperature to 160F requires a lot of energy.
Keeping 8000 gallons at 160F requires little to nothing.

Where is your heat going? Are you dumping water, or recirculating?
What volume of liquid product is being heated? And then air cooled, could recover some of the heat.
Reverse-flow heat exchanger is one approach. Passing bottles through a cooling tank and using heat pump to recover from that tank to the pasteurization bath is another.

Possibly evacuated tube collectors would be useful, good for the temperature in question.
 
Hedges said:
Heating 8000 gallons of water from earth temperature to 160F requires a lot of energy.
Keeping 8000 gallons at 160F requires little to nothing.

Where is your heat going? Are you dumping water, or recirculating?
What volume of liquid product is being heated? And then air cooled, could recover some of the heat.
Reverse-flow heat exchanger is one approach. Passing bottles through a cooling tank and using heat pump to recover from that tank to the pasteurization bath is another.

Possibly evacuated tube collectors would be useful, good for the temperature in question.
Click to expand...
That is the fun part - the water is continuously heating a stream of approximately 20 gallons per minute of cold (34F) product, entering the tunnel. :)
 
Commercial heat pump powered by solar sounds like a great option. Could possibly go grid tie and use that as your battery.

www.bosch-industrial.com

Air to Water Heat Pumps | Heat Pumps | Products | Commercial & Industrial

www.bosch-industrial.com www.bosch-industrial.com
www.carrier.com

Air-to-Water heat pumps and chillers | Carrier Finland

Carrier air-to-water heat pumps are designed to meet current and future regulations for energy efficiency.
www.carrier.com www.carrier.com

Any interesting article I skimmed that may be useful
www.sciencedirect.com

Photovoltaic thermal (PV/T) system assisted heat pump utilization for milk pasteurization

In this study, a hybrid photovoltaic-thermal heat pump system, supported by a four-pass economizer and a PV/T panel, has been installed to pasteurize …
www.sciencedirect.com www.sciencedirect.com
 
Cold beer enters, hot beer leaves. Push the hot water in opposite direction across the bottles, reverse flow.
Then run the somewhat cooled water in a trough back to other end, and run beer bottles through it. Reverse flow, now you have hotter water, less hot beer.
Use a heat pump to chill a water bath, depositing the heat in the hot bath. Pass beer bottles through it.

Should only have to put in a bit of energy to make up for what was lost.
 
Hedges said:
Cold beer enters, hot beer leaves. Push the hot water in opposite direction across the bottles, reverse flow.
Then run the somewhat cooled water in a trough back to other end, and run beer bottles through it. Reverse flow, now you have hotter water, less hot beer.
Use a heat pump to chill a water bath, depositing the heat in the hot bath. Pass beer bottles through it.

Should only have to put in a bit of energy to make up for what was lost.
Click to expand...
This is actually the way they are designed! The zones / bays each have a twin. The hot cans are showered with cold water from the incoming stream of product, which pre-heats that water for cans entering the tunnel. Similarly, the hot cans are cooled with cold water from the incoming stream of cas.

See this video around the 30 sec mark:

Unfortunately there is an impressive amount of heat needed to maintain this system, even with the cooling zones being used.
 
I'd consider solar thermal and solar-driven heat pump. Solar panels feeding a resistance heater is just too inefficient at your scale.

I assume it's a closed system, with water just cycling through repeatedly. Plus a little added to make up for evaporation. What's the temperature of the water entering and leaving the boiler?
 
Solar generators are only 25% efficient are sun-to-water panels more efficient? if they are then I would look at that type of panel.
 
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