Making the Case for Short-Term Solar Forecasting in Plug-and-Play Remote Microgrids

The microgrid market is tilting toward solar PV generation as a preferred resource. This is especially the case within the context of remote microgrids due to the economic advantages these systems present from an ongoing operations and maintenance perspective. A concentrated effort to move closer to plug-and-play microgrids is also underway, with a variety of vendors touting this approach.

One can make the case that displacing high cost diesel fuel with fuel-free solar is a valid value proposition on paper. However, a variety of ancillary technologies can also be integrated into a remote microgrid setup to transfer this concept into economic savings in the field. Such integration could displace as much diesel as possible while also limiting wear and tear on fossil fuel generators and batteries. Yet, the hype surrounding the dynamic duo of solar plus storage is obscuring the fact that different tools can help build a market for microgrids, including short-term solar forecasting.

A Game Changer in Australia

The Commonwealth Scientific and Industrial Research Organization (CSIRO) of Australia has helped develop a plug-and-play microgrid offering that marries low cost short-term solar forecasting with load optimization and diesel scheduling innovations. The game changer is the ability to integrate low cost short-term solar forecasting into remote microgrids featuring ever increasing solar PV penetration over time, with early tests showing a 97% reduction in high ramp rate events and fuel savings of almost 8%.

Solar forecasting falls into two categories: long term and short term. Long-term forecasts look out over a period of time (such as a week) to optimize resource scheduling. This forecast is more relevant to grid-connected solar PV resources. Since these forecasts look out over a longer-term time horizon, error rates tend to be lower because the forecasts are far less granular than short-term solar forecasts.

Remote microgrids cannot sell any services back to a grid operator; thus, the prime focus for remote microgrids featuring high penetrations of solar PV is short-term solar forecasts. Fluctuations at this scale can lead to blackouts or inefficient use of scarce and expensive diesel fuel.

According to the analysis Guidehouse Insights performed for CSIRO, it appears the key to commercial success of short-term solar forecasting is minimizing capital cost and error rates. One could argue that short-term solar forecasting should be the first response to managing the variability of solar energy, since it is far less costly than major hardware investments like advanced batteries.

Short-Term Forecasting Adds Value

The short-term solar forecasting technology embedded in the plug-and-play microgrid solution from CSIRO is well-suited to Australia. It also offers other forms of value. For one, it can be used in the planning process to shape the initial design. First Solar claims it can get within 1% accuracy of annual energy estimates from available solar resources, but the company has difficulty sizing batteries properly since short-term solar power production is too variable. The technology being developed by CSIRO can address this gap, developing better estimates of required capital costs during the design phase for better battery sizing.

Finally, short-term solar forecasting technology can also be an important tool utilized outside of a remote microgrid application such as in the case of virtual power plants (VPPs). Australia is emerging as a hotspot for VPPs, too. In fact, CSIRO is sponsoring a free event focused on VPPs on December 1. Australia just may be the center of digital grid innovations.