The end of generous feed-in tariffs is a great opportunity for installers and retailers to push the benefits of sophisticated solar and storage monitoring systems, writes Steph Bond-Hutkin.

Many Australians who invested early in solar have enjoyed earning money from their systems, or at least seeing much lower electricity bills, thanks to government solar incentives including bonus feed-in tariffs. Those bonus FiTs ended on December 31 for more than 200,000 Australians, with additional schemes expiring over the next few years.

Solar power systems traditionally haven’t been installed with solar or energy monitoring, and many Australians haven’t been aware of their system performance. For those solar owners, the bill shock in 2017 could be even greater. These changes present an opportunity for committed solar retailers to reconnect with their customers and to engage with others left unsupported, to ensure their systems are performing at their best.

The solar incentives and rapid up-take of solar was great for the renewables industry but created a lot of competition around price. This has resulted in a significant number of Tier 3 or lower quality systems from less credible manufacturers being installed. These lower quality systems have a higher failure rate – both the inverter and the solar panels themselves. In fact, 14% of solar power systems in Australia are currently not working at all.

The industry is justifiably concerned about the potential for damage to its reputation from underperformance from the lower-quality systems. Also, all solar power systems, whether they are high quality or not, can be subject to other failure points including inverter faults and errors, micro-cracks, gradual degradation, moisture ingress, incorrect installation, suboptimal positioning, soiling and other ailments.

Don’t be shady

One of the most significant barriers to solar performance is shading. The neighbouring tree that was no issue at installation may now have grown to the point that shading on panels is providing significant reduction in output.

But how do solar owners know if and when these faults occur? Some diligent individuals check the lights and data on their inverter regularly to ensure that it is functioning, but the inverter lights and data alone won’t tell you if you have shading issues or soiling on one panel. Perhaps it’s the inconvenience and fatigue of keeping tabs on your solar power system that is the real issue.

The majority of solar owners have a set-and-forget approach to their solar; in fact they’ve been led to believe the system will be trouble-free for a lifetime. As a result, most solar power systems have no reliable monitoring or fault alert mechanism.

It’s only when a quarterly electricity bill arrives that they may (or may not) have noticed a discrepancy in production. Some may put it down to fewer sunny days, and wait for the next bill, by which time they have become used to the new solar figure. Those noticing no solar production at all may contact their installer, who may refer them to their manufacturer, who may refer them back again; or they may have an electrician visit only to be unable to identify the issue with their system. It’s an expensive and time-consuming problem when there are no diagnostics.

In the US, it’s a different story. More than 95% of residential rooftop solar is owned by a third party and leased to the homeowner. The solar system is a business proposition, and for that reason the business owners (the solar third party leasing companies) make absolutely sure that their solar systems are functioning at maximum capacity. Nearly all residential solar systems have one or more forms of monitoring to pick up faults, and to provide the business owners with valuable information about their customers’ solar production and consumption habits. Using these insights, they can provide accurate advice on increasing their solar system size to match their energy usage.

Australian solar retailers, who are in the business for the long term, benefit the same way when they provided their customers with a monitoring solution. With monitoring, solar retailers remain in contact with their customers, they will benefit from increased referrals and have the opportunity to upsell to the same customers on new services, including storage. Solar owners are happier, too – they feel their investment is protected, they can know exactly how much solar they are producing, and how they are using energy within their home. Importantly, they should also know when their system starts underperforming, or not working at all.

Smart monitoring solutions such as that provided by Solar Analytics can tell you more about a system than its output. If a system is underperforming, a monitoring system can tell you what is wrong and what to do about it.

Let’s take a look at some of the system fault or failure causes that affect Australian solar power systems. We’ve covered product quality, but there can be other causes of solar system under-performance that can affect any system.

Negative effects

As well as shading, soiling can have a serious effect on the performance of solar panels. Regular maintenance will keep the effects of soiling to a minimum but requires information and when a clean is needed and discipline to safely clean panels.

Solar panels have a remarkable 25-year warranty, and most have been designed to last for even longer. However, there are a number of issues that can cause under-performance or early failure that require sophisticated analysis to identify.

Possible degradation causes include micro-cracks, delamination, hotspots, high resistance, shunting and potential induced degradation (PID). While identifying underperformance is challenging, diagnosis of the cause is next to impossible without time series data that is available with monitoring.

PID, almost unheard of until five years ago, appears as a loss in output power. PID has become increasingly prevalent with the move to transformerless inverters and can be accelerated by high system voltages as well as Australian coastal climates of high temperatures and high humidity. PID is covered by product warranty but needs to be detected in a timely manner. Monitoring will identify underperformance and smart monitoring can identify PID as the cause of underperformance.

Micro-cracks are small cracks that can appear in solar cells, often caused by poor handling processes prior to or during installation. Sometimes appearing as “snail trails” these micro-cracks can affect both energy output and system lifetime, but in many cases performance is unaffected. It’s important to determine whether the micro-cracks are impacting the system performance, as it is not cost effective to replace well-performing modules.

While quality modules can be expected to operate for over 20 years, inverters have lifetimes of only seven to 10 years. As a result, inverter faults account for almost 50% of major solar system failures. Inverters typically fail fast; when an inverter fails, the whole system shuts down and produces zero energy, but failed inverters can go undetected for months. If the failure occurs (and is detected) in the inverter warranty period, the problem can be addressed properly to meet the customers’ needs – delays can add costs and reduce customer confidence.

Outside of solar panel and inverter faults, other failure modes include problems with the AC or DC isolators, as well as incorrect or faulty installation. Oftentimes, the solar owner is never aware of the under-performance as generation may be no different from the time of installation.

Good monitoring will include solar energy production and energy consumption in the home. Research shows consumers who are aware of their usage are more likely to make changes to their daily behaviour to reduce consumption, with one study showing “contextualized feedback and targeted energy-saving tips” encouraged savings of 4-12%, and in some cases much higher.

Being aware of production and usage is the first step to significantly increasing customer value from solar, so providing solar owners with their solar production and energy usage data as well as their performance could exponentially increase their benefits from investing in solar.

Once a solar owner is aware of exactly when their solar production ramps up and ramps down during the day (their solar profile), they are quickly empowered to run appliances at the right time. Helping a customer understand their solar profile empowers them to make decisions around using energy that can hugely reduce reliance on the grid and use every precious drop of solar production.

The same rings true for solar owners with batteries. Common sense tells us that battery owners should use their solar generation to charge their battery and then use the stored energy outside of solar-producing hours. Beyond this, with accurate data, a battery owner can see once their batteries have charged to capacity; that’s valuable solar energy that can be used during the day.

Wake-up call

As Australian households that have lost their initial, generous feed-in tariffs move from gross metering (exporting all their solar energy generated) to net metering (using their solar energy first on-site before exporting any excess), they will need to change their energy consumption behaviour to marry their usage (and/or battery charging) with their solar producing hours, and do it efficiently.

Smart installers and solar retailers will want to work with these customers to help them make the most of their solar. More efficient use of solar is a win for the industry, for solar owners and for the electricity retailers facing challenges with peak usage.

 

Steph Bond-Hutkin is marketing director at Solar Analytics.