Should I wait to buy solar panels?

Like all emerging technology-based businesses, the solar industry continues working on technical improvements. According to physicists, the theoretical maximum possible efficiency of a solar cell is 31%. Current laboratory cell efficiencies are hovering around 24%. So there is some room for growth in efficiency, but as the maximum efficiency is approached, each incremental increase is smaller and harder to achieve than the previous one.

Today, low-cost crystalline solar cells are by far the most dominant technology type available, holding 85% of total market share. Numerous laboratories continue to experiment with alternative technologies that could exceed the 31% efficiency cap of standard crystalline silicon, but none of these are close to commercial readiness. Any new start-up technology promising a significant efficiency boost would face serious cost hurdles and a long timeline to compete with crystalline silicon on a lifetime cost-of-energy basis.

While manufacturers have continued to improve solar panel efficiency, they have found more efficiency (and more savings) in reducing their manufacturing costs. As solar panel prices drop, it is that manufacturing efficiency, and the growth in scale of solar manufacturing operations, that are driving those cost reductions. Solar panel prices are not likely to drop much further, because if they did, the manufacturers would be forced out of business.

Will solar panel prices continue to drop?

Solar panel prices have been falling ever since the technology was invented. 40 years ago the solar cells alone (not counting the other components) cost $2,000 per watt. Today, an entire system, including permitting and engineering, can be built for about $2 per watt. The previous two years alone saw a nearly 50% reduction in solar panel prices.

However, as solar panel prices fall, the dollar amount of each percentage point becomes smaller and smaller. Today’s panel prices are so low that many solar panel makers are struggling to remain profitable. The solar panel manufacturing sector has entered a tough period of mergers, acquisitions, down-sizing and right-sizing. Currently, we are in a period of overcapacity on solar panels. How this will affect prices in the future is not clear, but solar panel prices have stabilized in recent months and could soon begin to increase.

Historically, the solar panels were the largest piece of the cost equation in a solar energy system. As a result, the total system price trends followed the panel price trends.

Today, the substantial drops in solar panel prices means that the solar panels now have a much smaller affect on the overall cost of a complete system. Costs of the other equipment (which includes racking, inverters, wires, and conduit) are tied to the cost of commodity metals like copper, and these prices are not expected to decline anytime soon. Labor prices, project management costs, and engineering costs are currently at their most competitive and will likely not decline further.

Meanwhile, increases in other project requirements (such as structural engineering and permit fees, and electrical safety and project oversight requirements) are gradually adding to the list of cost items incurred on any project.

On the whole then, the price of a solar system is expected to remain fairly constant for the foreseeable future. Any reductions are projected to be small, while the possibility of price increases becomes more real as the market shakes out.

Can solar panels damage my roof?

Will solar damage my roof? The short answer is no. In fact, the reverse is true—by shading the roof from the sun’s rays and from the damaging effects of wind, hail and debris, the solar array will actually increase the life of the roof beneath it. And the panels themselves are quite durable—about as hard to break as a car windshield.

As experienced, certified installer, we take great care to ensure no damage is done to the roof during the installation or anytime thereafter. With the exception of large businesses, we generally sell one solar system to each customer, and therefore live and die by our reputation and word-of-mouth marketing. We work very hard to ensure that each and every one of our customers is satisfied with their solar system results.

Prior to the solar installation, a structural engineer evaluates your roof to make sure it can support the solar array. This evaluation considers both the weight of the array and the potential uplift due to wind. We make sure there is no way that solar will damage your roof.

Solar modules are mounted parallel to the roof with a 1-to-3 inch gap between the roof and the modules. In this configuration, the wind forces are not extreme and are easily handled by any roof that was built to code. Nonetheless, on every job we rely on a professional structural engineer to evaluate the specific site and ensure that the roof and the array comply with all the local wind requirements in the building code and will be able to withstand all expected winds.

In addition to the structural evaluation, we take great care to ensure every roof penetration is watertight. Our crews are experienced with all types of roofing; we fully flash every roof penetration using standard roof flashings. We have built over 350 solar systems in our 14 years of operation and we have never caused a roof leak. Not one!

What are the best solar panels?

For our solar panel  installations, we are very careful to find the very best solar panels based on reliability, performance, and long term value. Trina solar panels, for example, are made by one of the world-renowned leading solar companies; they have been listed at either #1 or #2 in the world for the past several years. We often use Trina panels because they are superior solar panels from a global leader. But we are not wed to them, and sometimes recommend other panels. It just depends on the specific project — each is customized to a great degree.

Many solar experts use the term “bankability” to refer to solar panel manufacturers that have proven to be reliable and stable, both in their product quality and in their overall company financial health. There are about 15 truly “bankable” solar panel manufacturers in the world, including Sunpower in the US.  Most of the U.S. solar panel companies are smaller companies, though some meet our requirements and are approaching bankability as discussed above.

In our experience, many “U.S. made” solar panels are not too different from the rest, in that most of the manufacturing is done by the same global supply chain. In some cases, the individual solar cells are made here in the U.S., then shipped overseas for final assembly into solar panels. In other cases, the companies are based here in the U.S., but actually manufacture overseas, where manufacturing costs are lower. This is not only true of solar panels — it is true of many products, especially technology products like computers, tablets, and smart phones.

When “U.S. Made” is a priority for a customer, we present them with options and show the cost differences. U.S. Made typically adds about 25 cents per watt to the customer’s cost.  That is a not a huge cost difference, but to an extremely cost-sensitive customer, it may make a difference.