What on earth is PHA?
PHA — polyhydroxyalkanoate — is a biopolymer that microbes make from plants — and that other microbes eat when you're done with it. It's the rare material that's truly compostable at home, industrially, and in the ocean. That's why we build every cupcasa cup from it.
From plant to cup to soil
PHA completes a genuine circle — every stage powered by biology, not petrochemistry.
Grown from plants
PHA starts with plant-based oils and sugars — renewable feedstock, not petroleum.
Brewed by microbes
Bacteria ferment those plant oils and store PHA as natural energy granules — the same way we store fat.
Shaped into cups
The biopolymer is harvested and formed into sturdy, food-safe cups. No plastic lining, no PFAS.
Returns to nature
When discarded, microbes recognise PHA as food and digest it — in soil, compost, or seawater. No microplastics left behind.
PHA vs. everything else
Not all "eco" cups are equal. Here's the honest comparison.
| Property | PHA (us) | PLA | Paper | Plastic |
|---|---|---|---|---|
| Made from renewable plants | If lined | |||
| Home compostable | ||||
| Industrial compostable | If lined | |||
| Marine degradable | ||||
| Soil biodegradable | ||||
| No plastic lining / PFAS | ||||
| Leaves no microplastics | Sometimes |
How to dispose of a cupcasa cup
Home compost bin
Toss it in your backyard compost — it breaks down with food scraps.
Industrial / commercial
Fits standard commercial composting collection where available.
Worst case: it escapes
Even if it ends up in waterways, PHA biodegrades — it won't linger for centuries.
Composting infrastructure varies by region — check your local guidelines. The point of PHA is that it breaks down responsibly across the widest range of end-of-life scenarios.