It has been reassuring to see the trend towards renewable energy developing over the past decade, proving that we are becoming more sustainable. Public opinion appears to have exerted sufficient influence to create a unified movement towards renewable energy.
Now that we are moving in this direction, it is becoming increasingly obvious that the devil is in the detail, as we are faced with the daily complex technical challenges that stand in the way of genuine sustainable energy production. Energy storage is an emerging technology that is playing an ever more vital role in overcoming these challenges.
With increasing levels of renewable energy being captured and funneled into power generation network grids, utilities companies are facing the challenging process of aligning intermittent renewable energy generation with their traditional energy supply.
The problem with intermittent renewable energy generation
This unpredictability causes two distinct problems:
- Many existing energy grid infrastructures are unable to accommodate the influx of renewable energy at peak generation times (e.g. sunny / windy days), resulting in waste. Any renewable energy supplied in excess of infrastructure capacity is rejected. In order to accommodate the renewable energy onto the grid infrastructure upgrades would be required, representing a significant investment.
- When lower levels of renewable energy are available to the grid, utility providers need to replace it with traditional energy, which can take time and incur additional costs.
The levels of waste combined with the risk of additional costs, mean that accommodating more renewable energy can appear a challenging proposition for utility companies. Unsurprisingly, this has caused many to look for solutions to overcome these grid constraints.
One company's energy storage solution
Westnetz, the largest distribution system operator in Germany (and a subsidiary of RWE International), was facing these challenges on rural grids due to increasing levels of solar PV generation on their network, particularly in summer months. The reinforcement of network infrastructure with new distribution lines and transformers would have been far from cheap in terms of time and labour. They were searching for an alternative solution which could be implemented until long-term infrastructure improvements could be undertaken.
Parker worked closely with Westnetz to provide a solution that ticked all the right boxes. The 250kW energy storage system, comprising a Parker 890PX series grid-tie inverter paired with LG Chem Lithium-Ion batteries, had a capacity of 1MWh storage, more than enough to support the local grid at peak times. This particular system was supplied in a 40 ft ISO shipping container, which can be relocated to different areas of the power grid as required. The system has enabled Westnetz to successfully store excess energy generated during sunny periods and release it back onto the grid according to demand.
Storage systems such as these provide utility companies with the flexibility to be able to accommodate the unpredictable supply of renewable energy, reducing the likelihood of curtailing solar PV generation whilst ensuring stable and consistent power for customers. The Parker / Westnetz collaborative project demonstrates the importance of energy storage in supporting emerging trends in renewable energy production, providing the flexibility to accommodate the sustainable energy progress that we are all hoping for.
If you are faced with the challenges presented by the growth in PV, learn more about solutions at the Energy Grid Tie Division website.