Solar, like wind, is an intermittent resource. That means that it’s only available when the sun is shining and clouds, along with the angle of the sun in the sky, and other factors, does affect its performance. NorthWestern needs to have reliable sources of energy available for customers at all times of the day and night to meet demand. So how can we satisfy some customers’ interest in solar energy and, at the same time, maintain the reliability and affordability that all customers expect?
The solar industry in Montana is currently about where the wind industry was more than a decade ago, so it’s a valid comparison. Although there were some early adopters that installed private wind, it was the “wind farm” approach that yielded the best results for all customers. And, as a result, we’ve learned that intermittent resources require additional always-available generation resources that can be called upon on short notice to maintain the consistent voltage necessary to provide reliable energy to customers. Currently, we rely on hydro, coal, and natural gas-fired resources to provide this type of energy on the system. This approach allows all of our generation assets to work well together to provide energy to customers when they need it and at the lowest cost.
While everyone can make educated guesses about how the resource might work for our customers, there’s no substitute for actual experience. Energy produced from the sun is similar in some ways to wind energy and different in others. So, we’re building pilot projects at various locations around the state that are designed to test various types of solar-related technology to further our knowledge of how this generation can be integrated into our electricity porfolio. We have committed to funding four separate projects that combined will help us evaluate the potential for solar to help meet our needs for reliable, affordable clean energy that benefits all customers.
By partnering with a few of our customers to test the application of new technology and approaches to energy services, we’re learning together how they may be of benefit to all customers. We’ve used these types of projects successfully in the past and we value the contribution of these customer-volunteers because their experience will result in smarter decisions.