After 4 years of severe drought and this year’s winter snowpack at a pathetic 8% of typical levels, it’s obvious that California will have to find real solutions as populations rise and the effects of climate change worsen. We rely on the High Sierras’ snowmelt throughout the year for everything from our green lawns and fresh food (throughout the US) to our hydroelectric power.
Governor Jerry Brown’s recent mandate for cutting water use by 25 percent was overdue and necessary, but communities will have to step up conservation efforts in a big way. Ever since the Governor’s big announcement ideas for how best to curb water use have been flowing. So why should PV solar power generation be at the top of the list? What does water conservation have to do with solar?
Solar is an increasingly important solution to water scarcity as well as energy security. With no sign of a solar slowdown in California—we are the first state to get 5% of its energy from solar—strong generation records are likely in coming years. While solar has been included in some communities’ plans to reduce water use (such as in the Los Angeles “pLAn“), many people are unaware of this solution. Communities, individuals and businesses installing rooftop solar can make a real positive difference for California’s dire water situation.
SolarEdge has gotten a fair amount of buzz this week thanks to their IPO, but it made us think that maybe it was time to revisit the question—who really has the edge: DC-to-DC “optimizers” like SolarEdge or Enphase microinverters?
|Which would you choose?|
|Enphase Microinverter||SolarEdge Optimizer|
In our view this is a bit of a “no-brainer” and it really comes down to the following three reasons:
Reason #3 - Integrated Grounding — In every solar array, all metal surfaces have to be grounded for safety. Enphase microinverters now feature integrated grounding, which eliminates the need for a separate equipment grounding conductor. SolarEdge does not have this feature and, depending on the jurisdiction, may require the use of a dedicated copper conductor to be run from one unit to the next. This increases both labor costs as well as part costs (copper is expensive these days!). Far better to have that grounding built-in at the factory than assembled on the roof.
Reason #2 - Easier Installation — Beyond the need for that equipment grounding conductor, the SolarEdge system requires the installer to not only mount the optimizers on the roof beneath each panel, but it also requires the installer to mount one or more heavy (51 to 88 pound) inverter(s) on the wall. In contrast, Enphase combines everything into one unit, so there are no heavy inverters to mount to the side of the client’s house.
Reason #1 - Greater Reliability —The number one reason for us at Run on Sun is the greater reliability you get from using Enphase. Frankly, the SolarEdge approach combines the worst of both alternative approaches (i.e., string inverters versus microinverters). You are still putting power electronics in the demanding environment of a roof, AND you have combined that with a single point of failure with the inverter back on the ground! When you use Enphase microinverters you eliminate that single point of failure and you are going with the industry leader in creating reliable, roof-mounted power systems.
Put all of that together, and we think Enphase microinverters provide the greatest value to our clients, which is why we feature them in all of our solar power systems, despite the occassional “buzz” other approaches might generate.
California has a long-standing reputation as a clean energy trendsetter. The state leads the nation in solar energy usage, energy efficiency overall, cleaner cars and energy storage. Currently on track to reach our goal of one third energy derived from renewable sources by 2020…Governor Jerry Brown kicked it up a notch in January by proposing California achieve an unprecedented 50 percent energy from renewable sources by 2030.
How will California accomplish such an ambitious target? This is the first in a series of blogs in which Run on Sun will addresss the challenges and possible solutions to reaching 50% by 2030 as opportunities unveil.
Ivanpah Solar Electric Generating Station
While rooftop solar is great for offsetting the usage of those fortunate enough to be able to invest in an array, most people tend to think utility-scale solar requires wide open spaces only available in remote parts of our state. The best example being Ivanpah, the world’s largest solar power plant - generating 345 megawatts on five square miles near the Cali/Nevada border. However, growing to 50% renewables using vast spreads of desert solar arrays has the potential to harm ecosystems. Far away solar farms also incur enormous infrastructure costs just to transport the power from the source to your toaster.
Fortunately a new study provides evidence that we needn’t look further than our urban back yards to find sufficient space for solar. Stanford researchers published their findings in the March edition of Nature Climate Change:
We tested the hypothesis that land, energy and environmental compatibility can be achieved with small- and utility-scale solar energy within existing developed areas in the state of California. We found that the quantity of accessible energy potentially produced from photovoltaic (PV) and concentrating solar power (CSP) within the built environment exceeds current statewide demand.
The urban landscapes we design are already great at capturing the sun’s rays, as evidenced by the heat island effect. It turns out we have the capacity to develop enough solar power to meet three to five times California’s demand just by utilizing urban flat spaces such as carports and rooftops. Obviously developing small and utility-scale solar in our built environment greatly improves efficiency and cuts infrastructure costs by generating power directly where it is used.
As the study’s authors note, it’s important to remember there will always be trade-offs. It’s not an all-or-nothing, urban-or-rural question but looking more closely at the opportunities for solar in our urban backyards should be a priority.
Run on Sun has been following the exciting developments of Solar Impulse since it’s prototype began its groundbreaking test flight across America in 2013.
After the lessons learned from the American flight, an upgraded Solar Impulse 2 was developed with a wingspan wider than a Boeing 747, more than 17,000 solar cells and 1,300 pounds of batteries. Amazingly, the aircraft still weighs no more than an average car!
Finally, this morning, on March 9th, 2015, Solar Impulse 2 and her team were ready to embark on their record-breaking aeronautical journey around the world. The first leg officially departed from Abu Dhabi at 7:12AM UTC+4. Landing in Muscat, Oman at 20:13PM UC+4 pilots Bertrand Piccard and Andre Borschberg rested for a few hours before continuing onward to Ahmedabad, India.
With a top speed of 50 mph, the entire circuit is planned to take four or five months before returning safely back to Abu Dhabi. You can follow their flight online as well as chat with the mission control center and view cockpit measurements like solar battery storage and pilot heart rate!
Solar Impulse is not only about accomplishing the first round-the-world solar flight. Behind the development of this technological feat lies a very powerful message. Piccard and Borschberg are using each landing as an opportunity to reach out to governments, NGOs, education centers, and the broader public to share what is possible with clean technologies.
“We shouldn’t be listing targets, but rather solutions – ways of meeting those targets. Because these solutions exist. Our society could already cut energy consumption in half by replacing old, outdated, polluting technology with clean technologies. Couldn’t we, all together, persuade governments to modify the legal framework so as to encourage the replacement of polluting technologies by cleantechs? That would at least make debates constructive and international climate conferences interesting.” - Bertrand Piccard
In conjunction with Solar Impulse’s round-the-world flight, the pilots started an online campaign called “Future is Clean”. In December 2015, they will share the largest collective voice in favor of clean technologies with global leaders at COP21, the United Nations Climate Change Conference in Paris. You can add your pledge and share with your networks at www.futureisclean.org.
This week the Run on Sun team participated in #NationWISE 2015, a national event engaging solar professionals and solar hopefuls to discuss ways to increase female representation in the industry. Nearly 350 women and men participated in similar roundtables in 15 different cities around the country! The event was put on by our friends at Women in Solar Energy (WISE), a great membership organization aiming to promote the involvement of women in all aspects of the solar industry.
Women make up 47 percent of the U.S. workforce overall, yet only represent 21 percent of the solar industry, according to the 2014 solar jobs survey (check out Run on Sun’s blog summarizing the census by the independent nonprofit Solar Foundation). The challenge to equal representation is two-fold. While it is difficult to attract women to an industry comprised of heavily male-dominated fields - engineering, construction, and sales - it’s also a considerable challenge to retain them. They frequently leave the industry to seek more supportive career environments elsewhere.
The solar industry is hurting by not attracting and retaining more female employees. It is a little known fact that women are often the key players in the decision to install a home solar system. Perhaps women’s longer-term concerns around family economics and the effects of climate change have something to do with this. In our discussion at NationWISE many examples were given where female sales representatives (although few in numbers) blew their male counterparts out of the water in terms of customer acquisition. Maybe female decision-makers respond better to female solar professionals? Some say women excel in sales due to traits such as better listening skills and attention to detail. Or perhaps consumers perceive female sales reps to be more trustworthy, sincere, and empathetic than a male sales rep.
This is all fairly anecdotal of course… I have yet to see any studies providing solid evidence on the matter. However, we at Run on Sun believe a gender balance brings a diversity of skills and assets to any team. We are certainly proud to have one of the few NABCEP certified female PV installers as our chief electrician. Not sure if it’s her gender that makes her supremely committed to making each project beautiful down to every minute detail, but it certainly doesn’t hurt. Whether in customer acquisition, installation, or management, qualified women and men both have a lot to offer.
The event produced a lot of ideas for improving the gender gap. WISE will be aggregating these suggestions from around the country and reporting the results in time for International Women’s Day on March 8th. Hopefully continued growth in the industry along with the awareness-building efforts of organizations such as WISE will improve the outlook for women. As a solar lady myself, working with a supportive solar company, I look forward to watching the industry develop into a powerhouse of talented and empowered men and women working together toward a future powered by the sun!