With the IEA pushing fresh measures to curb oil use and tighten global fuel efficiency standards, attention is shifting toward companies that help cut energy waste rather than pump more crude. That policy turn is reshaping where capital flows and which business models feel the pressure. This article walks through three stocks exposed to that news and explains how each could either benefit or face new questions in your portfolio.

The three stocks below are a starting sample. The full screen surfaced 50 more publicly listed energy efficiency companies with similarly detailed stories that are not covered here. To identify your own highest conviction angles on this theme, head straight into the Global Energy-Efficiency Technology Providers screener.

Delta Electronics (TWSE:2308)

Overview: Delta Electronics is a Taiwan based manufacturer of power supplies, thermal management, automation and building solutions that help customers use electricity more efficiently in data centers, factories and commercial buildings. Its products range from high efficiency power modules and cooling systems for AI data centers to drives, controls, LED lighting and building management systems that support tighter energy use in industry and real estate.

Operations: Delta Electronics generates most of its revenue from the Power Supply and Spare Parts Business Group at about NT$337,932 million and the Infrastructure Business Group at about NT$226,211 million. It has smaller contributions from the Automation Business Group at about NT$57,611 million and the Transportation Business Group at about NT$31,676 million.

Market Cap: NT$4,532.7 billion

Delta Electronics gives you direct exposure to two themes at once: energy efficiency and AI data centers. The company sells high efficiency power and liquid cooling systems that align with the IEA focus on lower energy waste, and recent earnings show revenue and margin performance from these solutions. At the same time, the stock carries risks that matter for long term holders, including reliance on Asian manufacturing, a weaker Mobility segment, and slower progress in higher margin service revenues compared with some peers. For investors willing to weigh these trade offs, the combination of scale, R&D focus and policy factors makes Delta Electronics a notable company to watch in this screener.

Delta Electronics is connecting energy efficiency to AI data centers at scale, while the real story lies in how its cash flows, margins and policy exposure fit together in the analysis report for Delta Electronics

Build your own energy efficiency shortlist

Delta Electronics and the two other stocks in this article all came from a single Simply Wall St stock screen, but the real edge is creating filters that reflect how you like to invest. Use our flexible Screener to mix metrics like valuation, growth, financial health and risks, or jump straight into our curated Investing Ideas.

AAON (AAON)

Overview: AAON is a Tulsa based manufacturer of high efficiency heating and air conditioning systems for commercial and industrial buildings, including rooftop units, heat pumps, data center cooling solutions and cleanroom systems that fit squarely into the push for more energy efficient HVAC and retrofit projects. It sells these products across sectors such as retail, education, healthcare, manufacturing and data centers through independent representatives, its own sales force and online channels in the United States and Canada.

Operations: AAON generates most of its revenue from AAON Oklahoma at about US$1.1 billion, with additional contributions from AAON Coil Products at about US$461 million and BasX at about US$535 million, partly offset by about US$199 million of eliminations.

Market Cap: US$6.7 billion

AAON gives you direct exposure to the energy efficiency theme through premium HVAC and heat pump systems. It also ties into data center cooling where electricity use and thermal management are under growing scrutiny after the IEA push on fuel efficiency. Recent momentum in BasX data center cooling and high efficiency rooftop units supports the story. There are real trade offs to weigh, including ERP rollout challenges, heavier capital spending and cash flow pressure. With policy support for cutting building energy use and a business model built around high efficiency equipment, AAON offers a focused way to play this theme, but investors will want to look closely at margins, backlog quality and funding before deciding how it fits into a portfolio.

AAON’s premium HVAC and data center cooling story is gaining attention, but the key question is how solid the fundamentals look beneath that interest. Get the fuller picture in the analysis report for AAON

Ningbo Deye Technology Group (SHSE:605117)

Overview: Ningbo Deye Technology Group is a China based manufacturer of solar inverters, energy storage systems and frequency conversion air conditioners, along with dehumidifiers and heat exchangers that support more efficient HVAC and industrial thermal systems. Its products are sold in China and overseas, giving you exposure to both renewable power electronics and energy saving climate control equipment in homes, factories and commercial buildings.

Market Cap: CN¥122.5b

Ningbo Deye Technology Group may be worth a closer look if you want a single company that brings together solar power electronics with energy saving HVAC and thermal equipment, at a time when policymakers such as the IEA are focusing on cutting oil use and improving efficiency. Investors may want to consider that earnings have grown in recent years and that analysts expect further gains, while valuation metrics suggest the stock is not priced at the top of the local electrical equipment peer group. At the same time, it is important to weigh governance questions, an uneven dividend history and a funding structure that leans on external borrowings, especially with profit margins recently under some pressure. The upcoming first half 2026 results on 27 August could be an important check on how these trade offs are evolving.

Ningbo Deye Technology Group blends solar electronics and efficient HVAC, yet its valuation story still feels underappreciated. Get a clearer sense of whether earnings and pricing truly align with the analysis report for Ningbo Deye Technology Group

Seeking Alternatives Before Momentum Takes Off

Fresh ideas do not stay quiet for long. Stocks move once the crowd catches on and edges from new themes can fade quickly. Scan these under the radar ideas and consider them before they gain broader attention.

• Identify companies leaning into new AI demand before wider attention catches them by using the curated 55 AI infrastructure stocks.
• Track early strength in companies tied to digital assets and blockchain infrastructure while this theme is still settling using the focused 20 cryptocurrency and blockchain stocks.
• Focus on producers with meaningful exposure to gold when sentiment shifts between fear and risk appetite through the targeted 32 elite gold producer stocks.

This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.