Why I Chose LiFePO4 Batteries to Power the Project

There is no way around it, extractive industries such as those of the mining of petroleum, coal, uranium, and yes… lithium have large-scale negative effects on our environment.

So, from that perspective, it could (and should) be said that the most environmentally sound manner of having a business that relies on these industries is to not have it. That is, that from an exclusively environmental perspective, it would be best if the coffee industry (which relies heavily on extractive industry [one could even make a strong case in labelling the agri-business methodologies in coffee growing to be an extractive industry in of itself]) ceased to exist.

However, we do not look at things from an exclusively environmental perspective. We must realize in our considerations that millions of people throughout the world depend on the continued existence of the coffee industry for their livelihoods.

In short, coffee is not going anywhere. (* / ** / *** / and many, many more. Simply do a Google scholar search for “coffee production climate change” and you’ll find some 438,000 results [admittedly, you’ll find a lot of “chaff” here, but also a lot of “wheat”. I personally tend to throw out any study that starts with a paraphrase to the claim “coffee is the second most traded commodity in the world after oil” – It is NOT. Not even close. And that usually gives me, perhaps unfairly, something of a “chaff filter”.])

So, if the ongoing existence of the coffee economy is taken as a given, the question then becomes “how do we continue to produce roasted coffee to customers while minimizing our environmental impact?”

It is here that we must concede that our impact will never be zero sum; as even putting a spade to ground will alter the tenuous equilibrium derived of millions of years of niche-making. So, to make the coffee economy continue whilst also being conscious stewards of the land, we must make a compromise between our environmental obligations and the demands of the consumer (economic obligations).

As for us here in the consuming countries, and personally as a roaster, the most immediate and basic need to make a coffee business work (other than coffee itself) is a heat source to roast the coffee.

The most ubiquitous heat source is, of course, the combustion of methane (CH4), more often referred to as natural gas (tangentially, a fascinating study conducted by Yale on the public perceptions of the terms “natural gas” and “methane gas” can be found here); and it’s easy to see why, it’s cheap to procure and relatively efficient in heat transfer.

However, methane is a fossil fuel whose extraction and combustion is extremely detrimental to every facet of our environment. Furthermore it is a greenhouse gas, some 25x (to 80x when viewed on a 20 year time-scale as opposed to the 100 year cycle used by the EPA) more potent than CO2 (here is a quick video on the “heat capturing” ability of CO2).

For these reasons, I chose to power my roaster with electricity (I hear you, person screaming “but where does that electricity come from??!!” Hold your horses. I’ll get there).

Electricity has the potential, unlike other heat-energy sources in the market, to be an incredibly clean fuel. However, it is unfortunately also true that most of the energy across the country is still derived from the burning of fossil fuels (60.3%). Here in Milwaukee, that number is even higher, with somewhere between 68.6% and 90.4% of our energy being derived from fossil fuels; depending on the derivation of ”Market Sources” at 16.0% and “Other” at 5.8%.

So, I knew that in order to maximize the relatively positive impact of utilizing electricity to power the operation, I would need to generate my own power. However, being at 44 degrees north, this decision would also mandate a means of energy storage. For it would be hard, especially in the winter months, to harness enough solar power at any given moment to continuously power the roaster.

Here too, unfortunately, we run into environmental concerns. As previously stated, lithium mining; and for that matter, the extraction of cobalt, lead, and other resources needed for common battery chemistries are all fraught with environmental, not to mention humanitarian, issues.

So, what then to do?   

(If I had lots of land and/or access to water or an artesian well I might be tempted to play with a less “COTS” [Commercial, Off-the-Shelf] solution, however…) We must therefore, once again, compromise.

If the continuance of the coffee economy is taken at a given, what chemistry will do the least amount of harm while giving us the needed amount of energy storage to produce a roasted product? Let’s see our options:

The most prevalent battery solutions in use today are Alkaline (single-use, Non-rechargeables like AA, AAA, C, D, etc.), lead acid (your [and full disclosure, my] internal-combustion engine car almost certainly has one), Lithium Ion (this is a blanket that covers a lot of different specific chemistries [LiCoO2, NMC, etc.], your phone and laptop run on these), and Lithium Iron Phosphate (though also technically a “Lithium Ion” battery, LiFePO4 batteries have stood out enough to become something of a category in of themselves, especially in solar applications. Those solar powered highway speedometers often use them).

Alkaline

This option was ruled out immediately.  It is untenable from every perspective; environmental, economic, and annoyance. Can you imagine replacing a battery bank’s worth of AA’s every half hour? Holy mackerel.

Lead Acid

Despite their particularly nasty chemical make-up, lead acid batteries had three huge pros in its favor; a much lower up-front cost, a protracted and proven track record, and a robust recycling infrastructure.

Lithium Ion (Particularly LiCoO2 and NMC)

These have a few major pros as well, namely their extremely high energy density (how much energy storage per kilo/lb, which is of particular importance in a mobile application such as this one). Also, their up-front price is low in comparison to LiFePO4 and they have a number of readily available “plug and play” solutions such as the Yeti Goal Zero series (which was the runner up in my decision making process), Bluetti series, and others.

Lithium Iron Phosphate

Despite the much higher up-front cost than the other options, these seem to me to be the best long-term investment (Battleborn website lists 80% initial capacity at 3000 to 5000 cycles). They last, under constant cycling, between 2 and 10 times longer than lead acid and between 2 and 5 times longer than NMC batteries (summary). Also, they are a more stable and less corrosive chemistry (i.e. safer) than either NMC or lead acid as they do not catch fire (higher “flash point”) nor leak poisonous residues and/or gasses when punctured, dropped, or otherwise mishandled. Lastly, they are capable of discharging to nearly 0% without damage to battery longevity. As a reference, lead acid batteries can only safely discharge to about 50%. What this means is that while a LiFePO4 battery and a lead acid battery may both say 100Ah, the lead acid is, in effect, 50Ah (usable energy) while the LiFePO4 is truly 100Ah (as shown in this video).

Overview

There are many other pros and cons to each system and I feel it important to state that none of these are “silver bullet” solutions (in fact, I find the very concept of a “silver bullet” solution to be paradoxical. For even if a solution works in a community, scaling anything up to serve 8 billion people is likely to be an ecological nightmare [even for something as ubiquitous as food]. This is why I buy into the “Think Little” ideal. The idea that many small scale solutions may be better than one giant, all-encompassing blanket “solution”. This goes not only for our power consumption needs, but our food as well, as eluded to in this wonderful essay by Wendell Berry).

For me, the decision to choose the LiFePO4 battery for was for a combination of the topics discussed; its longevity, its safety, its depth of discharge, its continuous amperage rating, its US-based operations, and a few more.  

However, it must also be said that there is a major problem in my ultimate choice.  This issue is centered around the fact that there is a conspicuous lack of an effective, large-scale recycling program. There are some startups attempting to take on this challenge (and others, and likely many others), but the amount of waste from EV’s and other commercial production is likely to overwhelm the amount of battery recyclers currently active, or even in early stages of development.

This said, I believe that they present the best environmental value for LM Coffee Project.

They allow me to operate at near capacity of my small roaster. Better still, they allow me to do so free of any ties to the local grid system which, as previously mentioned, generates up to 90.4% of its power using fossil fuels.

Lastly, to answer the question: are the batteries the best economic decision for the project when compared to alternatives, such as burning natural gas?

The answer is no.

However, it is important to remember that we do not look at things from an exclusively economic perspective. We must realize in our considerations that millions of people throughout the world depend on the continued existence of their local ecosystems for their livelihoods.

In short, we must learn to balance our potential economic prosperity with our environmental obligations.