Guinness Global Investors recently released its "Guinness Sustainable Energy Fund" Q3 2026 investor letter. A copy of the letter can be downloaded here . The fund faced a challenging third-quarter 2026 investment environment as rising interest rates, persistent inflation, and a rotation away from growth stocks weighed on renewable-energy and electrification shares. The Fund declined 8.1% during the quarter, underperforming the MSCI World Index, which gained 1.9%, as higher Treasury yields pressured interest-rate-sensitive industrial and utility holdings and an AI-related sell-off affected electrical equipment and semiconductor investments. Despite the quarterly weakness, the managers believe the sector's long-term fundamentals remain attractive: wind and solar electricity costs have declined substantially, more than 90% of utility-scale renewable projects commissioned in 2025 were cheaper than the lowest-cost fossil-fuel alternative, and the Fund's expected annual earnings growth over the next three years increased to around 17%. Looking ahead, Guinness remains constructive on renewable generation, grid investment, energy storage, and electrification, arguing that the Fund's forward price-to-earnings multiple fell from 18.7 times at the end of June to 16.4 times at the end of September even as expected earnings growth improved, creating a more attractive valuation opportunity for investors seeking exposure to the energy transition. In addition, please check the Fund's top five holdings to know its best picks in 2026.

In its third-quarter 2026 investor letter, Guinness Sustainable Energy Fund highlighted stocks like Owens Corning (NYSE: OC ). Owens Corning (NYSE:OC) manufactures building and construction materials, including insulation, roofing, and composite materials. Its business is exposed to building efficiency, construction activity, and renovation demand. The one-month return of Owens Corning (NYSE:OC) was -8.49% while its shares traded between $97.53 and $159.91 over the last 52 weeks. On October 14, 2026, Owens Corning (NYSE:OC) stock closed at approximately $111.26 per share, with a market capitalization of about $8.98 billion.

Guinness Sustainable Energy Fund stated the following regarding Owens Corning (NYSE:OC) in its Q3 2026 investor letter:

"Higher rates weighed on building efficiency names as the outlook for construction and renovation activity remained weak. US mortgage rates rose sharply, from around 6.5% to over 7.2%, reversing a three-year downward trend and weighing on housing affordability. Owens Corning (NYSE:OC)(-26.1%) gave back some of the premium that had built up following reports of an unsolicited takeover offer from Carlisle."