BLDP vs FSLR: Correlation
How closely do Ballard Power Systems, Inc. (BLDP) and First Solar (FSLR) trade together? Their weekly returns over three years give a correlation of 0.46, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BLDP and FSLR?
Over the past 3 years, BLDP and FSLR moved with a correlation of 0.46, which is moderate. Little has changed lately, as the 1-year reading of 0.43 lands near the 3-year figure. Over 5 years the correlation is 0.46, and the annualized covariance of weekly returns is 1715.3 %².
Among the 23 assets we track against BLDP, FSLR ranks #9 by 3-year correlation. Over the last 12 months BLDP came out ahead by 5.9 percentage points (+15.8% against +9.9%).
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
BLDP vs FSLR: side by side
| BLDP (Ballard Power Systems, Inc.) | FSLR (First Solar) | |
|---|---|---|
| 1-year return | +15.8% | +9.9% |
| 5-year return | -85.8% | +119.6% |
| Volatility (ann.) | 66.3% | 56.2% |
| Beta vs S&P 500 | 1.62 | 1.14 |
| Max drawdown (3Y) | -76.4% | -60.0% |
| Market cap | $0.7B | $22.6B |
| P/E (trailing) | – | 12.7 |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | Information Technology |
Year-by-year returns
| Year | BLDP | FSLR |
|---|---|---|
| 2022 | -61.9% | +71.9% |
| 2023 | -22.8% | +15.0% |
| 2024 | -55.1% | +2.3% |
| 2025 | +53.0% | +48.2% |
| 2026 | -7.9% | -19.6% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BLDP and FSLR good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.46 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between BLDP and FSLR?
The BLDP/FSLR correlation stands at 0.46 on a 3-year window (1 year: 0.43, 5 years: 0.46), computed from weekly returns as of 2026-08-27.
Is FSLR a good diversifier for BLDP?
Yes, to a useful degree: a correlation of 0.46 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.46 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: BLDP correlations · FSLR correlations
