3 ms·

Any comparisons with aerogel?

• nkurz 7y ago
  They are hard to compare directly, since the "magic" of down is its compressibility, whereas aerogels are typically rigid. Eiderdown is actually on the lower end of elite downs as far as loft, which is measured as "Fill Power" (FP): https://www.researchgate.net/figure/Fill-power-values-from-eider-down-in-20-different-nests-in-two-colonies-17-and-18_fig5_315823797 https://www.researchgate.net/figure/Fill-power-values-from-e... That said, there is a new synthetic sleeping bag insulation that is using some amount of added aerogel fragments. Compared to that, high FP goose down of 800 or 900 FP is still much better insulation per ounce: https://backpackinglight.com/forums/topic/new-ul-synthetic-insulation-from-primaloft/#post-3537976 https://backpackinglight.com/forums/topic/new-ul-synthetic-i.... I don't know if it's in any way a useful comparison, but combining the two links, one might conclude that eiderdown at a 500 FP is about as insulating as PrimaLoft Gold with added aerogel.