TrainChaser
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Yesterday, September 28, I did my matte-black-painted one-gallon plastic water bottle experiment for a source of hot water without a stove or fire.
* The temp was 70F, clear, sunny.
* The bottle was a clear plastic Crystal Geyser from the local Dollar Tree; I had melted a hole in the lid with a hot nail for the soil thermometer, and dropped the thermometer shaft into the hole.
* The surface was an old black asphalt driveway with weed dust stuck in the cracks.
* The control was an unpainted bottle of the same kind (label turned away from the sun).
Due to my faulty memory problems, I put both bottles in position the night before.
Results:
I forgot about them until noon.
* At noon, the temp in the black bottle was 105.
* At 1 p.m. (I set the kitchen timer) the water temp was 110.
* At 2 p.m. the water temp was 110.
* At 3 p.m. the water temp was 110.
* At 5 p.m. the water temp was 105.
That showed a 40-degree rise in temperature from the ambient air temp.
The control bottle was a complete waste of time because I forgot to put a hole in the lid to measure the temperature of the water. I could have just unscrewed the lid, but I didn't.
I left the thermometer in the black water bottle (I forgot it) and when I went out at 9:30 this morning to retrieve it, the air temp was 50 and the water in the bottle was 60.
My hot water heater (set to the lowest normal setting to save energy) hadn't been used yet this morning, so I ran the hot water tap to wash dishes, filled a ceramic mug and let it warm up for a minute, then dumped it and refilled it with more hot tap water and stuck the thermometer in it: 115F.
The Web says the ideal hot shower temperature is somewhere between 100-110F.
More work is needed.
* If the air temp had been 90F, would the temp in the bottle still have gone up 40 degrees?
* If the bottles had been laid on their sides (exposing more surface to the sky), would that have made a difference?
* If I had washed the driveway the day before to clean off the weed/wood debris to make it blacker, would it matter?
* If a curved, foil-covered arc stood immediately behind them, would it have made a difference? Or a pile of bricks formed into a short wall? Or a pile of bricks painted black? Or set close to the front of the S-facing garage door?
* SODIS says the maximum volume for that method of water purification is 2 liters/quarts; would the smaller size have changed the results?
Next time, I will prepare the clear bottle properly and compare. I would hate to discover that I had painted 50 bottles black when I could have gotten the same results from clear ones. Of course, unpainted, they would be subject to more UV damage, but I could paint them in pretty colors instead so they didn't look like goldfish caskets.
I should do this with the four seasons and see what happens. I wouldn't be hoping for much in winter, but the black paint might prevent the water from freezing on marginal days. That's W WA winters, not ND winters.
* The temp was 70F, clear, sunny.
* The bottle was a clear plastic Crystal Geyser from the local Dollar Tree; I had melted a hole in the lid with a hot nail for the soil thermometer, and dropped the thermometer shaft into the hole.
* The surface was an old black asphalt driveway with weed dust stuck in the cracks.
* The control was an unpainted bottle of the same kind (label turned away from the sun).
Due to my faulty memory problems, I put both bottles in position the night before.
Results:
I forgot about them until noon.
* At noon, the temp in the black bottle was 105.
* At 1 p.m. (I set the kitchen timer) the water temp was 110.
* At 2 p.m. the water temp was 110.
* At 3 p.m. the water temp was 110.
* At 5 p.m. the water temp was 105.
That showed a 40-degree rise in temperature from the ambient air temp.
The control bottle was a complete waste of time because I forgot to put a hole in the lid to measure the temperature of the water. I could have just unscrewed the lid, but I didn't.
I left the thermometer in the black water bottle (I forgot it) and when I went out at 9:30 this morning to retrieve it, the air temp was 50 and the water in the bottle was 60.
My hot water heater (set to the lowest normal setting to save energy) hadn't been used yet this morning, so I ran the hot water tap to wash dishes, filled a ceramic mug and let it warm up for a minute, then dumped it and refilled it with more hot tap water and stuck the thermometer in it: 115F.
The Web says the ideal hot shower temperature is somewhere between 100-110F.
More work is needed.
* If the air temp had been 90F, would the temp in the bottle still have gone up 40 degrees?
* If the bottles had been laid on their sides (exposing more surface to the sky), would that have made a difference?
* If I had washed the driveway the day before to clean off the weed/wood debris to make it blacker, would it matter?
* If a curved, foil-covered arc stood immediately behind them, would it have made a difference? Or a pile of bricks formed into a short wall? Or a pile of bricks painted black? Or set close to the front of the S-facing garage door?
* SODIS says the maximum volume for that method of water purification is 2 liters/quarts; would the smaller size have changed the results?
Next time, I will prepare the clear bottle properly and compare. I would hate to discover that I had painted 50 bottles black when I could have gotten the same results from clear ones. Of course, unpainted, they would be subject to more UV damage, but I could paint them in pretty colors instead so they didn't look like goldfish caskets.
I should do this with the four seasons and see what happens. I wouldn't be hoping for much in winter, but the black paint might prevent the water from freezing on marginal days. That's W WA winters, not ND winters.