SPEAKER REPORT: Andreas Helwig “Solar System at USQ & In General”

Few of our speakers would have as many titles, letters, research and lecturing qualifications as our expert speaker on solar energy. As an electro-mechanical engineer with his research area in sustainable energy systems and storage, Andreas was a key committee member and consultant for USQ’s solar panel covered carpark project, along with rooftop installations at the Ipswich and Springfield campuses. The Toowoomba solar carpark was conceived in 2010 and completed in June 2017 with a view to minimizing electricity costs, off-setting Greenhouse gases, and utilizing it as a real-life teaching model. LED lights are installed underneath and operate with motion sensors at night. Panels have also been installed on the USQ library and other build-ings. The university is now investigating the possible merits of adding storage batteries into the mix later on.

Andreas’ address included many electrical technical statistics re watts and battery types, etc. that flew over many of our heads, so I’ll list here general points he made regarding solar systems:

§  USQ panels have a 17% sunlight to power conversion efficiency. Recent space programs now have up to 30% conversion rates.

§  Panels are made to withstand hail damage, but their strength varies with country of origin.

§  The university panels have a nine-year payback timeframe, with approx. 20% greenhouse reduction.

§  All panels slowly ‘degrade’ and become approximately only 80% efficient.

§  Andreas is studying manufacturing faults (discovered using infrared photography), as well as weak-nesses in cell to cell and panel to panel connections and transmission.

§  Panel output is affected by conditions in the vicinity including reflected heat off bitumen or adjacent buildings, dust, smog, diesel particles (very damaging), sand, pollution, and humidity (the drier, the better; therefore, panels on island nations can disappoint with high humidity and storms).

§  Red dust is less of an interference than sand dust.

§  Battery storage systems can last up to 15 years, but are very variable to date.

§  The placement of the system’s inverter should be in a cool/south side position. Maximum heat tolerance for them is 45⁰C but that temperature and higher jeopardizes performance.

§  Nickel-ion battery has the longest cycle life with 100% power in yielding 70% power out.

§  Lithium-ion battery with 100% power in transmits 80% out, but has shorter life.

§  Batteries don’t perform well in the cold.....Electronics don’t perform well in the heat.

§  Deeper daily battery discharge = shorter battery life, i.e.. 80% discharge.

§  Lower daily battery discharge = longer battery life, say discharging only 30%.

   (You can relate these last two points to your mobile phone habits and recharging intervals!)

The one question Andreas wouldn’t commit on is when and how to wash solar panels!..... Except he stresses to  turn off your system before anyone washes it !!

At the end of Andreas’ address, I’m sure we all had an increased appreciation of just how much electrical and technical knowledge is involved in the production of solar energy.

(Report by Lauren Marlatt)