Introduction:
In the field of electrical engineering, power transmission can be carried out using both direct current (DC) and alternating current (AC) lines. While both types of lines have their own advantages and disadvantages, it is important to understand the power transmission capabilities of each.

Explanation:
DC lines carry more power than an equivalent AC line. This can be attributed to several factors:

1. No reactive power:
In an AC transmission line, there is a component called reactive power that is required to maintain the electric and magnetic fields associated with the alternating current. This reactive power does not contribute to the actual power transfer but still needs to be transmitted. In contrast, DC lines do not require reactive power, allowing for a more efficient power transmission.

2. Reduced losses:
AC lines have higher transmission losses compared to DC lines due to the skin and proximity effects. These effects cause the current to concentrate near the surface of the conductor, leading to increased resistance and power losses. DC lines, on the other hand, have comparatively lower losses as the current flows uniformly through the entire cross-section of the conductor.

3. Voltage drop:
AC lines experience higher voltage drop compared to DC lines. This is because AC lines have inductive reactance, which causes a voltage drop across the transmission line. In DC lines, there is no reactance, resulting in lower voltage drop and hence more power being transmitted.

4. Power factor:
AC lines have a power factor, which is the ratio of real power to apparent power. The power factor is always less than or equal to 1, indicating that not all the apparent power is converted into real power. DC lines, on the other hand, have a power factor of 1, meaning that all the power transmitted is real power.

Conclusion:
Considering all these factors, it can be concluded that DC lines carry more power than an equivalent AC line. DC transmission is often preferred for long-distance power transmission and high-voltage direct current (HVDC) systems are used for efficient power transfer over long distances. However, AC transmission still remains the dominant choice for most power transmission and distribution systems due to its ease of generation, transformation, and distribution.