Why low efficient solar panels are a waste of money

Buying a less efficient solar panel now will likely result in a poor long term outcome for consumers, as it will prevent them from expanding their solar system in the future, when one needs to create more electricity for batteries and electric car. Solar panels come as a 60 cell version and a 72 cell version and the inefficient panels have a rating of 250 to 270W in the 60 cell (1m x 1.6m) or around 320W in the 72 cell (1 m x 2m). To buy a future proof system now one needs to consider keeping reserve capacity available on the roof for future expansion.

The reason is that residents will have solar on their roof in future years and will not only be able to generate electricity but also to charge the battery system for their home electricity consumption at night, and to generate electricity for their electric cars.

One of the quickest and easiest ways to act on climate change will be to move from fossil fuelled cars to electric cars in the next 5-8 years. It will only make a CO2 difference if the power for these electric cars is gained through renewable energy, otherwise they would just be shifting from oil to coal powered electricity. It therefore comes as no surprise that many car manufacturers now have an electric car in their model line-up. LG most recently has signed up with 14 out of the top 20 car manufacturers for future battery supply for their electric vehicles under development. It goes without saying that Tesla is very active in this space.

Most people would need a range of around 80 -100 km per day for their electric car, and using the current electric car as an example that would need a minimum of 12-14 kW/h of electricity to travel this distance. So, most homes, especially the ones with 2 cars would need to generate at least 24KW/h for the cars and they would also aim to get a further 20-25 kWh for use in their home, as this is the average home’s electricity consumption.

In the near future people are likely to have battery storage charged by their solar energy system during the day which would then recharge their cars at night. Many people may actually choose to be disconnected from the grid or operate within micro grids. So, if we add up the minimum energy requirements with a comfortable buffer for cloudy days etc. in the future one would need a solar system that can generate at least 50 kW/h per day.

To create 50kW/h of electricity one needs a 10-14 kW solar system, depending on the location in Australia. Today most solar systems sold are around 3 to 5kW. The advertised and very cheap 250-275 Watt panels (as they offer old technology) will not allow such a big system to be installed on many local roofs. One would need to install over 50 panels to get to the ideal system size and most residential roofs are simply not big enough to have so many inefficient panels fit.

So by choosing the highest output panel today, when you just buy a solar energy system, before batteries and electric car, getting a highly efficient panel means customers will be preserving valuable roof space for future expansion. It’s a bit like buying a more expensive upgradable computer, rather than a cheaper one that becomes obsolete quickly, the next time Windows does an update.

Some manufacturers are already working towards 360/400 Watt 60 cell panels and 400 plus 72 cell panels in the very near future and one of the stand out companies having poured money into research for batteries and high efficiency panels is LG Electronics. From an initial model of 60 cell – 215W in 2011, LG via house research is currently offering a 320W NeON2 on the same physical size as the 260 watt panels. In 2017, they launched a new step forward: the 60 cell – 360W – NeON R.


LG also has some very good battery storage products coming in the RESU range, which are designed to last 20 years and which have just started to arrive in Australia. If you do the math, the increased efficiencies start to make sense. Let’s assume a family drives about 15,000 km per year, that’s about $22,000 in fuel costs over 10 years, and if they face an annual electricity bill of $2,000 for their home, that is a further $20,000 spent in that period, giving them a $42,000 expenditure over 10 years. If they invest this sum into solar and batteries and electric vehicle charging there could be savings even at today’s pricing.

Buy a high efficient solar panel now, save roof space to expand in the future with batteries and even then keep some roof space reserve so when electric cars come you can get fuel from the sun. The future energy revolution is much closer than many people imagine. So get an efficient panel now and save your valuable roof space, for future system and battery expansion.

By Markus Lambert