Group 1 - The solar sector in the US experienced a significant rally, with multiple stocks showing impressive gains [1][3] - Sunrun, the largest residential solar installer in the US, saw its stock rise by as much as 42%, closing with a gain of 32.82% [3] - SolarEdge Technologies increased by 17.10%, while NextEra Energy, the largest developer of solar and wind energy, rose by 4.39% [3] Group 2 - The Invesco Solar ETF also performed well, closing up 8.79%, marking its best single-day performance since May 2024 [3] - The surge in the solar sector is likely linked to a large tax reduction and spending bill signed by Trump on July 4, which allows solar and wind projects starting construction within 12 months to qualify for tax credits [3] - There are over 2,500 wind and solar projects in the US that could be affected by this legislation, with a total generating capacity equivalent to 383 nuclear power plants [3] Group 3 - Recent adjustments to guidelines by the US Treasury and IRS have removed the previous "5% standard" for large projects, now requiring developers to demonstrate "substantial physical work" is ongoing [4] - Small solar facilities under 1.5 megawatts can still apply under the "5% expenditure" standard, while residential solar projects remain eligible under previous guidelines [4]