smallsolar

I have a #coldframe made of perspex and wood which due to its location gets a lot of sun in the morning, I've added some temperature sensors and it can get temps of over 40C at times, this is only for 30-60mins and then it gets a bit of shade and cools down.

I'd like to try and take advantage of this burst of heat but spread it during the day - so Mastodon friends - would adding some thermal mass help, perhaps a plastic bottle of water painted black?

What's nice is that I have sensors so should be able to monitor effectiveness!

#diy
#maker
#gardening
#greenhouse

Mar 29 at 3:00pmWeb
Show threadsmallsolar1d ago
just to add context, here is the temperature graph from the last 7 days, the green line is the internal temp on the esp32 while yellow is a SHT30 temp in a white case (so more accurate).
Show threadGuillaume Rossolini1d ago

@smallsolar if I’m reading this correctly (not my area), water or iron are great at holding heat? Followed by earth

[edit] NB the notations are in French in the link, so a comma in a number means units and decimals, not thousands

https://fr.wikipedia.org/wiki/Capacit%C3%A9_thermique_volumique

Capacité thermique volumique — Wikipédia

Show thread𝓻𝓻𝓪1d ago
@smallsolar stones, tiles have high thermal mass
Show threadsmallsolar1d ago
@rra interestingly I have some slate tiles which are a little cracked so had to be replaced off our roof, they should fit in nicely
Show threadAndy1d ago
@smallsolar Brick painted black would be better. Lower specific heat capacity than water. Interested to see the results, whatever you use!
Show threadsmallsolar1d ago
@andy I've got some slate tiles which would fit in well, let's try that. Of course today is a cooler day so experiment will have to start tomorrow
Show threadDon Ray1d ago

@smallsolar

Thermal mass should help even out the lows and highs. It’s definitely counterproductive if the plants burn up.

Show threadLarry1d ago
@smallsolar
Using waterbottles to moderate night temperatures is known; your data would measure whether they reduce the mid-day spike. Please advise at the end of season?
Show threadsmallsolar1d ago
@quoidian absolutely, will report back with data
Show threadclew1d ago

Especially if you can put the black heat storage exactly where the early light hits. Max fancy: insulate the storage when light leaves, open the insulation at dusk.

I notice you have some answers assuming you want to reduce greenhouse temperature overall and others assuming you want to even it out. Differentnproblems!

@smallsolar

Show threadsmallsolar1d ago
@clew I'd say that I want to even it out, at least at this time of year, as full summer hits I might need to reduce the temperature - got some plans for that
Show threadSun Cloud22h ago

@smallsolar We would brew manure “tea” between pepper plants for thermal mass and to hold a frost blanket away from the plants on nights where temperatures dropped.

Later in the season the tea was, ah, consumed … but not by humans.