Did you know one hour of sunlight can meet global energy needs for an entire year? However, effectively harnessing solar power and running a profitable solar plant is no easy task. There are many things operators can do to improve the output of their solar plants, thanks to the advancement of technology. Despite these efforts, there are factors that remain out of an operator’s control such as the amount of sunshine and power demand.
Stop night-time losses
To further enhance the output of the solar plant, productivity measures can be developed, especially during the night. For example, while solar plants “go to sleep” after the sun sets, connected transformers still consume electricity. This small loss — a couple of kilowatts each night — can add up to big costs — up to as much as $800,000.
Yet, switching transformers off can cause voltage spikes, deteriorating the insulation material over time. It also produces large current inrush when reconnecting to the grid, which can be six times higher than normal transformer operation. All this adds extra mechanical stress to the equipment, shortening its life cycle. That is why many operators have, in the past, chosen instead to leave it on and allow electricity to slip away each night.
But operators shouldn’t lose sleep over this, as GE has a solution that can help reduce some of those incremental costs being incurred. In the course of switching the transformer on or off, inverters provide reactive power to magnetize the transformer. Once the voltage is synchronized with grid level — meaning voltage levels on both sides are equal — transformers can then be connected or disconnected smoothly and cleanly. By operating in such a controlled way, stress on the system is minimized, which should help equipment achieve a longer lifespan.
So, in a nutshell, by using intelligent controls to simply disconnect transformers automatically at night, no-load losses are eliminated and significant savings can be achieved.
Accelerate field installation
Further cost savings can be made by wrapping the equipment into a container. How? A container can be used both as a skid and enclosure, providing both the base for the equipment and its protection. The container itself can be shipped, therefore reducing transportation costs.
The pre-assembled and pretested solar container requires minimal field work during installation on-site, which greatly reduces risk and time needed during commissioning. Every piece of equipment is already set up inside the container, meaning just the cables need to be connected and the power switched on. Moreover, as transformers are premagnetized and synchronized, it allows multiple systems to be connected to the grid simultaneously, further accelerating field commissioning.
The same principle can be applied in the event of an outage. As the entire solar plant can be connected to the grid all at once, it achieves a faster recovery.
SiC technology to provide efficiency boost
Efficiencies can also be gained during the daylight hours too, through the use of innovative technologies. By using Silicon Carbide (SiC) — a synthetically produced crystalline compound of silicon and carbon — in inverters, it can achieve power conversion efficiency up to 99 percent EU level. This may not sound like a huge amount, but if a 100-megawatt plant was 1 percent more efficient, it could generate extra power that equals to up to $2.5 million in extra lifetime revenue.
By using technology and innovation to reduce daytime and nighttime losses as well as to accelerate commissioning time, solar farm operators can begin to cut down their list of worries and focus on what’s important.
Designed specifically for utility-scale solar farms, GE’s Power Conversion business’ LV5+ eHouse solution coupled with SiC technology is ready to help operators make the most of what they can control and gain higher energy output over the lifetime of the power plant.