Micro energy harvesting: Correlation
Prices it moves with, and why
Micro harvesters turn small amounts of light, heat, vibration or radio waves into power for sensors and wearables. Their price depends on device volumes, chip costs and the materials in thermoelectric and piezoelectric elements.
No public price Micro energy harvesting has no public monthly price series: Niche components sold inside devices; no public price series.What its price moves with
Thermoelectric generators that run on body or machine heat mostly use bismuth telluride. Bismuth is a by-product of lead and tin refining, so its supply depends on those metals rather than on demand from harvesters.
No public price for bismuth, so the link is explained in words only.Tellurium is the other half of bismuth telluride and is recovered from copper refining residues. Thin-film solar panels compete for the same limited supply, so their growth can tighten tellurium for thermoelectric devices.
No public price for tellurium, so the link is explained in words only.Most vibration harvesters use lead zirconate titanate ceramics because they give the strongest output. The lead content is tiny, so its price matters little, but rules restricting lead in electronics push research into lead-free piezo materials.
Not enough overlapping price history to measure.Harvesters compete with coin and other primary cells in remote sensors. When battery replacement is costly, for example in sealed or distant devices, a harvester that lasts the life of the product becomes worth its higher upfront price.
Not enough overlapping price history to measure.Harvested power arrives in tiny, irregular bursts, so devices store it in supercapacitors or thin-film cells. The cost and self-discharge of these small stores often decide whether a harvester design is practical.
Not enough overlapping price history to measure.Indoor light harvesters are small solar cells, often amorphous silicon or dye cells tuned for lamp light. Their costs benefit from the wider solar industry's progress in materials and manufacturing, even though the products are very different in size.
No public price for solar photovoltaics, so the link is explained in words only.How to read these numbers
Correlation of monthly changes (the number in the coloured pill) compares how much each price moved, month by month, since 2006 or the first month both series exist. It runs from −1 to +1: near +1 the two usually rise and fall in the same months, near 0 there is no link, and a negative number means they tend to move in opposite directions. Above 0.7 is strong, 0.4 to 0.7 moderate, 0.2 to 0.4 weak.
12-month changes compare year-on-year moves, which shows whether two prices share the same cycles even when the month-to-month noise differs.
Price function is a straight-line fit of the two prices on logarithmic scales: price ≈ k × (partner price)β. β is how much this price moves, in per cent, for a 1% move in the partner over the whole period, and R² is the share of the variation the fit explains. Two prices that both drift up with inflation can fit well without any real link, so read it together with the monthly correlation.
Lead or lag checks whether the monthly correlation is clearly higher when one price is shifted by 1 to 6 months.
Correlation is not cause. The reasons on each card explain the economic link; the numbers show how strongly it has shown up in prices. Proxy series are US producer price indexes or related prices and can blur the real link.
Data: World Bank Commodity Price Data (Pink Sheet), October 2026; US Bureau of Labor Statistics producer price indexes, IMF primary commodity prices and US EIA prices via FRED, Federal Reserve Bank of St. Louis, retrieved November 2026. Calculations by this site.