Update: New upgrades will reduce your mood loss by one third, meaning 0.75% loss per minute instead of 1.5%. I've redone the numbers using the 0.75% figure because if you are worrying about how much energy to buy you probably have a lot of upgrades and ultimately we'll get there. I realize that a lot of people are having trouble finding the third card because it's super rare, though.
Also now updated for changes to Rookswort.
When you increase your maximum energy you also increase your maximum mood. I already wrote about maximum mood and how it was strictly a negative thing. As it turns out, your maximum mood is still tied to your maximum energy, so mood can be thought of as a penalty you have to suffer through in order to get more energy.
I'll warn you up front that in order to prevent this post from getting very, very long it is probably one of my heaviest on math and shortest on explanation. If you aren't that interested in the heavy math part then you can skip through to the examples or even straight to the fascinating conclusions. If you want a further clarification of any of the things I've done in this post, just ask.
First, let's assign a currant value to imagination so that we can compare the imagination we'll lose from not having full mood to the cost of drinks. There are a number of ways to turn currants into imagination with very different returns, but I think it is safe to say that the standard is shrine donations. With extremely hallowed shrine powder you can donate 100 currants worth of goods and get 72 imagination back for it.
Of course if you really were donating only 100 currants then you'd be foolish to use the shrine powder. That's not just a frivolous statement, either. A use of shrine powder costs around 400 currants and there is a limit to how much you can donate at once. If you donate 10000 currants worth of goods at once then the cost of the powder would reduce your imagination per currant to 69% of your donation.
Since 72% is probably a little high, we'll use 70% to reflect that fact that you do need to use that powder. A very high level glitch with huge donation caps may be able to approach 72% imagination in currants, but not everyone will be able to and no one can quite get there. Of course there is also the issue that the things you are donating likely are not worth their full street value to you. If you are crafting something specifically to donate it then your alternative to donating is likely selling, and if donating was your best option then it probably means your alternative is selling to the tool vendor for 75% of the list value. Thus we are choosing between getting 70 imagination or 75 currants, and choosing the former quite frequently. Thus, we will confidently say that glitchen are willing to pay 1.07 currants per imagination.
As I usually use 0.8 currants as the price of an energy, and as this price is based on the market of the game where people actually pay that price frequently, we can then say that one imagination is worth around 1.34 energy.
Mood Loss and Restoration
You lose mood at the rate of 0.75% of your maximum mood per minute of play when above 90% mood. So after thirteen minutes you are no longer getting full imagination for your actions.
In order to get mood back you can drink, but unfortunately mood is quite expensive. Taking the price of each drink, subtracting off the value of the energy and imagination that it provides, and then dividing that into the mood that it restores we get the price of mood in currants. This price, it turns out, is extremely variable, ranging from 0.1 (Too-Berry Shake) to 0.88 (Slow Gin Fizz). There is also the outlier, coffee, which returned 2.4 mood per currant (though it restores mood slowly), and the Savory Smoothie which returns an amount of mood based on currant mood.
You can also meditate, though meditating is rarely practical except when crafting. There is also rookswort, which reduces the rate at which your mood goes down in the first place, exotic juice which gives you better imagination return when you have low mood and, of course, the option of ignoring mood and just getting less imagination.
Animals and Trees
If you are mostly harvesting from animals and trees then generally you are not going to have to worry about mood. It is when you start to craft or when you are mining the mood becomes a factor. From my own observations I typically gain about 1.5 mood a second while running around harvesting from trees and animals. If I needed more I could be petting piggies as well as nibbling them, and even massaging butterflies. These activities generate good amounts of imagination so it's not nearly as wasteful as it may seem.
1.5 mood a second is 90 a minute, which is 0.75% of 12000, so unless my energy tank gets extremely high, I'm still not going to be worried about mood as long as I'm out harvesting from plenty of animals.
If you are running a resource route collecting just trees then you earn around 0.37 mood per second, which is 22.2 mood a minute, which would support a tank of 2960 energy. That's a lot less, but usually on resource routes there are animals around too, so you can quickly catch up using them if you want to.
When you are crafting you can be meditating as well (if you didn't know this already, start doing this immediately). Assuming you have meditation rank 3 and that you are meditating as often as possible without slowing down your crafting the amount of mood you are able to restore depends on the amount of time you are able to spend crafting a single stack of an item.
For example, if you are crafting White Gas then making a stack takes about twenty seconds. That means you will start a stack, meditate for twenty seconds, interrupt that meditation to start the next stack, and then the next stack without meditating. You will meditate about one third of the time, which restores 60 mood per minute. That's enough to keep your mood up with a tank of 6000. If you craft a stack of eggs you get to meditate a little bit closer to the ideal of around 23 seconds out of each 43. Still, that isn't much better than half the time, so half the time is a reasonable benchmark to use.
There is also focused meditation, which isn't necessarily enough better to justify giving up the energy. Suppose you are transmuting a stack of gas without upgrades. It takes roughly 20 seconds to create 20 transmuted gas. That means you could meditate for 20 seconds every other stack. With focused meditation you could either start 10 seconds into every other stack or just meditate every third stack. So with regular meditation you meditate half the time, but with focused meditation you meditate only a third of the time - the result being you get exactly the same amount of mood. If, on the other hand, you have an upgrade allowing 30 gas to be processed at once you end up getting meditate about 23 out of 54 seconds regardless of which kind of meditation you have, so focusing gives 50% more mood than regular meditation.
Generally giving up the energy from meditation is going to make buying more maximum energy much worse, so I'm going to assume that we would rather use regular meditation.
For most crafting it is fairly safe to say that meditation can sustain a mood tank up to 8000.
Mining is basically the whipping boy of activities when it comes to mood. You get no mood at all from mining so you'll have to keep up your mood completely with drinks or other means.
Cost of Mood
If you need to increase your mood by about 12 a minute then coffee is the cheapest way to do it, though it will also take up a fair bit of bag space. 12 mood a minute is enough to increase your energy tank by 1600, so that could sustain a miner with up to 1600 mood, or sustain a meditating crafter with 1600 more mood than meditation can manage. This would cost 5 currants a minute, about 1 currant a minute per 320 maximum energy.
To sustain an extra 36 mood per minute you can drink slow gin fizz. That adds another 4800 to the energy tank you can manage at the cost of 45.6 currants a minute.
Assuming you are keeping yourself at 90% mood or higher, a savory smoothie will restore you to full and sustain your mood at full for as long as the buff lasts, regardless of your mood pool size, then you'll have 12 minutes before your energy decays again and you have to drink another to top up. With an 80 second buff that means drinking one every thirteen minutes and 20 seconds. They cost 96 currants so that's 7.2 currants a minute, which pretty much rules out Slow Gin Fizz.
Rookswort halves your mood loss for 5 minutes but its price is more volatile. There is a market for it on auction, so auction price is the best way to determine its value. Currently Ecurnomics shows a value of around 90, but given the recent nerf I'd expect that to drop to historical lows of around 60 (unless it has the perverse effect of raising prices because the supply drops more than the demand or because people are using twice as much). Rookswort will give you 24 minutes at full mood before having to use it, which would increase your time between smoothies to 25 minutes and 20 seconds. That's saving you 3.4 currants per minute, but costing you one fifth of the price of a rookswort per minute. Unless rookswort drops in price to 19 or less, it's not going to be a good idea to use it. Since that's completely out of the question, we can pretty much say rookswort isn't even a consideration anymore.
In short, if your mood is a little higher than you can sustain then you should be drinking coffee. If your mood is much higher than you can sustain then use either savory smoothies.
Is Mood Worth the Cost?
If keeping up an unlimited mood tank costs 7.2 currants per minute and we are willing to spend 1.07 currants to buy an imagination then keeping mood up has to be earning us 7.7 imagination per minute to be worth doing. That means if you are earning less than 1.28 imagination per second then you should consider letting mood drop rather than paying to keep it up.
But what would you be doing that would earn you so little imagination? There is practically nothing in the game that produces so little. Basically it would only be if you are doing something that you are not skilled in.
Given these calculations, Exotic Juice, which only gives 75% imagination return with low mood, is out of the picture.
Is a Larger Energy Tank Worth the Cost
For the first 1600 energy above what can be sustained through the activity itself, you pay 1 currant per minute per 320 energy. Beyond that maintaining mood costs about 7.2 currants per minute regardless of how much you have.
So is 1 currant per minute worth 320 maximum energy. Well, in previous posts I generally talked about the value of maximum energy in terms of energy per game day, not energy per minute. Of course you can't just divide by 320 to compare the two because most of us don't actually play all four hours of any given game day, let alone every game day.
Two go back to our example glitchen, suppose we take the glitch who averages about 2 hours of play per game day that they play (except for gardening the morning, but they don't play long enough then to use their full energy or to suffer greatly from mood decay, so that can be ignored) and teleports about 2 times on each of those days. According to our basic calculation this means that 320 more energy would be worth 52.2 energy per day to this glitch. The glitch, however, also uses a flap of no-no every other day they play to craft with and their energy is currently low enough that the 320 additional energy would increase the amount they get to spend during no-no crashes. That means that it would provide another 252 energy every other day, or 126 per day. So the 240 energy gives a total of 178.2 energy per game day.
Let's say this glitch spends about 60% of their time gathering from animals and trees, 30% crafting, and 10% mining. They also organize bags and their house but they are cautious to do this at the end of the day so that they can ignore their mood completely. If their energy is lower than about 6000 then the extra mood will only be affecting them while mining, which means 1 currant per minute 10% of the time they play, or about 12 minutes per game day. They are paying 12 currants for 178.2 energy. Not a bad deal.
If the energy would also mean they couldn't sustain their mood through meditation while crafting (maybe they don't have a high rank of the meditation skill or maybe they already have nearly 6000 energy) then they would now be paying 48 currants for 178.2 energy. Still not a bad deal, if it was as simple as that.
Of course with the fact that this glitch needs to set aside a bag slot for a stack of coffee might make us ask if the good price on 178.2 energy is worth a bag slot. The answer to that will depend on your level and your wealth.
What about savory smoothies? How much energy do we have to have before 7.2 currants a minute starts to pay off?
Well to make the example as positive for the smoothies as possible, let's assume that the glitch in question basically mines all the time and uses no-no to crush rocks. Because they are using no-no to crush rocks they can add at least 78.8 extra energy per 100 maximum energy they buy unless they have a staggeringly high energy total already. If they have less than 3000 energy then each 100 energy is worth about 178.8 energy extra from the no-no. Furthermore because they don't really leave the mines they almost never teleport, say 0.3 teleports a game day. With two hours played per game day, this would mean 100 energy it worth 111.8 energy per game day if they have over 3000 energy, or 211.8 energy per game day if they have under 3000 energy.
They have to keep their mood up the entire time they play, so 7.2 currants per minute comes out to 864 currants per game day. Of course increasing the amount of energy they have doesn't increase this cost. To make it worth 864 currants per game day they should be getting at least 1080 energy out of the deal. But as all energy up to the 3000th point is worth 2.118 energy per game day each, they would only need an energy tank of 509 to reach this.
Of course this is pretty extreme. What about someone who only mines about a third of the time, makes us of one no-no to crush rocks every other day, crafts about a third of the time as well and also teleports an average of twice a day?
If this person was drinking smoothies to keep mood up while mining then they would be spending around 288 on smoothies per day. If they were also doing it while crafting then they would be spending 576 per day. Of course if they are doing it while crafting then we know they probably have over 6000 energy. With two teleports a day, two hours, played and no-no every other day their energy per day return on maximum energy is 0.554. So with 6000 energy they would be getting 3324 energy per day from their energy tank. That's worth 2660 currants. With only 2000 energy they would be getting half as much energy from their tank but also paying half as much for their smoothies because they wouldn't be drinking them while crafting. With less than 720 energy they would be getting a bad deal from those smoothies, but the remedy for this is to have more energy, not less.
What about someone who never uses no-no powder or get out of hell free cards to increase the value of their energy tank? Whether or not it is worth it to keep their mood up would depend heavily on how often they teleport and how much they play per game day. With one or two teleports in a one hour game day the energy per day relative to energy tank size would be .53, pretty close to the example above and so they could easily benefit from more energy and be able to pay for it. On the other hand, if the basic calculation shows your energy per day to be less than .3 then you would need to have 2125 energy to pay make one hour of smoothies per day worth it. If, like Glitch A, you were only getting 0.16 energy per day for every maximum energy you have, then in order to sustain one hour of mining on smoothies you would need to have an energy tank of 3375 to make the cost of the smoothies worth it. Of course if energy is a negative for you to begin with then no amount of it will be a good thing.
If you spend your time gathering from trees and animals then just keep your energy under 12000 or so and you'll be fine.
If you spend your time crafting and meditating while you craft then keep your energy tank under around 8000 and you'll be fine there too. Note, though, that 8000 requires fairly ideal conditions - and here ideal means impossible. If you don't want to run out of mood while crafting 6000 is probably a lot safer.
If you are mining a lot then you'll have to pay to keep your energy up. With very low energy you can use coffee, but for the most part you should be using rookswort or savory smoothies to maintain your mood. Given that you are doing this, the more energy you have the better since that means you get more bang for your buck from the mood maintenance. However, you still have to keep in mind how much value you are actually getting for your maximum energy. If maximum energy has a poor return for you then it may be vary hard to make the activity justify the cost of the smoothies.
Lastly, mood is mostly going to be sustainable if energy is more of a benefit to begin with. That means using no-no or get out of hell free cards to increase the value you are extracting from your energy tank. If you are using neither of these things then unless the number of times you teleport per day plus 3.2 times the number of hours you play per day is less than around five buying energy will never end up paying for itself in terms of increased mood cost.