As the demand for data centers increases, so does the need for energy to power them. In the last several decades, solar power has re-emerged as a viable solution for meeting the energy needs of data centers. With the right infrastructure and technology, solar power can be an effective and efficient solution for powering data centers.

Solar power captures the sun’s energy and converts that into direct current (DC) electricity.  This DC electricity is then converted into alternating current (AC) electricity, which can be used to power typical electrical devices and facilities, including data centers.

The most obvious advantage is that solar power is a renewable and sustainable source of energy.  Another advantage of solar power for data centers is that it can be used to reduce energy costs, and as data centers consume a significant amount of energy, this energy consumption is a major expense for data center owners & operators.  By using solar power, data centers can reduce their reliance on grid electricity, which can also be subject to price fluctuations.  Using solar power can also help data centers reduce their carbon footprint, and by using solar power, data centers can significantly reduce their carbon emissions, helping to mitigate the effects of climate change.

While there are advantages to using solar power for data centers, there are challenges that must be addressed, including the variability of solar power.  Solar power is dependent on sunlight, which varies depending on the time of day, season, and weather conditions.  This variability makes it difficult to rely on solar power as a consistent means or secondary source of energy for a data center.  Another challenge of using solar power for data centers is the cost of installation; while solar power can provide cost savings over time, the initial cost of installing solar panels and the necessary infrastructure can be significant, especially tying into critical systems.  To address this challenge, some owners have turned to leasing or power purchase agreements (PPAs) to finance their solar power installations. These arrangements allow data centers to access solar power without the upfront costs of installation.

To use solar power in a data center, several infrastructure requirements must be met, such as the installation of the panels, inverters, and connection to the power systems.  A solar power system for a data center may incorporate energy storage to help with peaks and sags.  

There are systems that can provide a capacity in modules of 300-500 kW of solar power, depending on the environment and systems, coupled with an energy storage capacity of 2 MWh.  While there is a storage capacity that might seem to be able to support a 2 MW data hall for an hour, or larger capacities for less time, the discharge rates must be taken into account.  In most cases, for a data center, this is compared to a typical UPS and battery system, where the batteries cover 5-15 minutes of full load to allow the generators to start operation.  This theoretically means the discharge for 2 MWh could potentially cover 8 MW for 15 minutes or even up to 24 MW for 5 minutes. 

However, the discharge rate on such a system cannot accommodate – yet.  The UPS systems internal to the data center and it’s operations are not simply replaceable in such a manner.  The intent may be there, but to rely on that type of system will need to be proven in an operational manner to ensure that long time loss of solar power will not compromise the battery storage or continuation of operations.