돈經濟

From the first half of 2026, the Korean stock market was dominated by semiconductors, led by Samsung Electronics and SK Hynix. As demand for HBM and AI servers exploded, the profits of both companies soared several times year-on-year, and their share of KOSPI's market capitalization at one point exceeded 50%. However, in July, the market experienced significant volatility due to concerns about a slowdown in AI investment (controversy over Meta's oversupply), National Pension Service rebalancing, and exchange rate fluctuations. In mid-August, it plummeted with rising US Treasury yields, only to rebound repeatedly with SK Hynix's announcement of a 40 trillion won share buyback and full cancellation.

As of the closing price on Friday, August 21, the KOSPI closed at 6,912.95. Samsung Electronics at 281,500 won (+3.87%) and SK Hynix in the 1.73 million won range (+2.31%) boosted the index, but leading power equipment stocks underwent adjustments. HD Hyundai Electric was at 718,000 won (-3.75%), LS ELECTRIC at 187,000 won (-6.12%), and Hyosung Heavy Industries at 2.721 million won (-4.76%). With semiconductor profit forecasts peaking this year and the growth rate potentially slowing next year, the market is already looking for what comes 'after semiconductors'.

The key is that AI doesn't end with software or chips; it requires physical infrastructure. The biggest bottleneck in building data centers is power, followed by cooling. Goldman Sachs estimates that major cloud providers will invest approximately $1.14 trillion (about 1,600 trillion won) in AI infrastructure next year. In Korea, the government is also promoting the construction of 8.4GW of AI data centers in the first phase, centered around SK, GS, and Naver, with a mega-project totaling 550 trillion won being discussed.

This trend is the most promising theme to follow semiconductors.

The clearest candidates are power equipment and cooling.

Demand for ultra-high voltage transformers and distribution equipment for data centers and the replacement of aging power grids are surging, especially in North America. HD Hyundai Electric has signed a long-term supply contract worth 1 trillion won with North American big tech companies, and Hyosung Heavy Industries and LS ELECTRIC have also seen a sharp increase in their order backlogs. Iljin Electric is accelerating its entry into the North American market by securing a 120 billion won order for 245kV ultra-high voltage transformers for a Canadian data center. With factory utilization rates high, supply cannot keep up with demand.

Cooling is also rapidly emerging. AI servers generate much more heat than general servers, so air cooling alone has limitations, and there is a trend towards liquid cooling (cold plates, CDUs, etc.). Samsung Electronics has decided to invest 280 billion won in its Gwangju plant to build a line for producing HVAC and cooling equipment for the German Fläkt Group. This is a large-scale investment in production facilities after 37 years, meaning that cooling equipment for AI data centers will be manufactured domestically. LG Electronics is also strengthening its related businesses.

This industry is already showing a rotational pattern where it performs relatively strongly during periods when semiconductors are 'resting.' However, stocks with high valuations may experience short-term corrections. Currently, it is at the initial stage of transitioning from 'order confirmation' to 'revenue recognition.'

Shipbuilding and defense are structural industries with different 'visibility.'

Shipbuilding has already secured 3-4 years' worth of order backlog. Orders for LNG carriers, coupled with the reorganization of the energy supply chain from the Middle East, have led to domestic shipbuilders almost monopolizing orders. The performance of HD Korea Shipbuilding & Offshore Engineering and Hanwha Ocean also exceeds consensus. If new momentum, such as engines for data centers, is added, it is evaluated that the mid-to-long-term visibility is even longer than that of Semi (Semicon-semiconductors).

The defense industry has a structure where demand is maintained as long as geopolitical tensions are not easily resolved. Exports of K9 self-propelled howitzers and K2 tanks are expanding beyond Poland to the Middle East, Central and South America, and Eastern Europe, and Hanwha's entry into North America is also becoming visible, as it secured a contract for a prototype of the US Army's next-generation self-propelled howitzer. Although short-term stock price movements are highly volatile, it is important that the order cycle has not broken.

Among construction companies, Hyundai Engineering & Construction, Daewoo Engineering & Construction, Daelim Industrial, and SK ecoplant, which have specialized construction capabilities for AI data centers, can benefit. Companies that integrate power input, cooling systems, and modular construction methods are at an advantage.

Expected changes by year-end

The biggest variables until the end of the year (December 2026) are the actual commencement of construction and the speed of order conversion. Once domestic AI data center projects begin full-scale construction, the earnings visibility of companies related to power equipment, electric wires, and cooling will improve significantly. The timing of North American orders being recognized as revenue is also likely to be concentrated in the second half of this year to early next year.

While semiconductors remain a key driver of the market, if the perception of 'peak growth rate in profits' spreads, funds could shift more rapidly to power, shipbuilding, and defense. Some brokerage firms, such as Kiwoom Securities, already point out that the upward revision in profit forecasts for the third quarter is greater for transportation, IT hardware, construction, and machinery sectors than for semiconductors. This is a period where sector rotation is becoming full-fledged.

The KOSPI has the potential to test the 7,500-8,000 range by the end of the year. However, if concerns about a resurgence in US long-term interest rates, the November midterm elections, and a slowdown in additional AI investment emerge, a pullback to the 6,400-6,700 range could occur. The exchange rate (won/dollar) is moving around 1,380 won, which is still favorable for export companies' performance.

Secondary batteries (ESS) could indirectly benefit if demand for power stabilization in AI data centers aligns, but currently, the pace of EV demand recovery and the shift to LFP are more critical variables. Biotech and cosmetics may see thematic rebounds, but it will be difficult for them to become leading sectors.

In summary,

Summarizing the analyses so far, the Korean stock market in 2026 still has semiconductors as its most powerful 'engine,' but it has entered a stage where the engine alone can no longer drive the index upward. The sectors to follow are power and cooling infrastructure, which are the physical foundations of AI, and shipbuilding and defense, which have already secured several years' worth of work.

Currently (end of August), semiconductor shareholder returns (SK Hynix's 40 trillion won share cancellation, anticipation of Samsung Electronics' follow-up measures) are supporting the downside, and the power equipment sector's order momentum is not yet fully reflected in stock prices. As the year progresses, as data center construction and power equipment deliveries become more visible, the assessment of them as 'the second semiconductor' is likely to gain more traction. From an investment perspective, rather than completely abandoning semiconductors, a portfolio that expands the AI value chain from chips to power/cooling to construction/shipbuilding seems reasonable. Volatility remains, but sectors supported by structural demand (power shortages, geopolitics, energy transition) will take over the baton from semiconductors.