The controversy around the draft AS/NZS 5139:2017 for the safe installation of battery systems highlights two competing interest groups.
- The first is the residential-based activist community that support ‘democratised energy’, ‘distributed energy’, and home-based solar with charging. This group also includes the supply and marketing firms and websites that sell into, market, and profit from the industry.
- The second group has a similar long-term objective of high-penetration RE, but believes that large-scale RE is going to be the most important route. This includes many commercial organisations, but also many non-commercially vested individuals and organisations.
Having scanned DR AS/NZS 5139:2017 and having participated in standards development, my sense is that the draft simply reflects normal safety concerns. Personally, I wouldn’t want 50 kWh of lithium batteries installed inside my home. However, there is a question of whether the draft is too conservative and onerous for smaller systems.
An iPhone has a battery of about 0.005 kWh, a Macbook about 0.08 kWh, but a Tesla Powerwall about 6.4 kWh. A home consuming the residential average of around 15 kWh and wanting to go nearly off-grid is going to need maybe 60 kWh of batteries. That is a lot of energy and lot of risk if something goes wrong. The draft requirements seem routine for a commercial environment. The problem is that the average householder does not see the need to apply commercial standards.
It is one thing to have a properly installed and maintained quality system, but in 20 years, how many systems will be around and who is going to maintain them? When the home is sold, will the new owners maintain the system? — the annual change over rate of Australian homes is 6 % with many homes changing owners in under 10 years. The life of batteries is probably going to be about 10 years. What about safe disposal? The structural quality problems in the residential PV market cause a loss of energy or poor warranty support, but an equivalent problem with storage has the potential to be more serious. Residential consumers are simply not in a position to do comprehensive due diligence of prospective suppliers.
A complicating factor is that a lot of people and firms are counting on making a lot of money out of the residential market and are going to scream loudly. I see this as a classic Baptists and Bootleggers issue – firms that are going to profit from the residential market portray themselves as having altruistic motives, while activist groups critique the profit motive of the utilities but seem oblivious to the commercial interests of the firms that will making unregulated profits from storage. Furthermore, risk aversion (of chemical and fire hazards) is often in the eye of the beholder .
I think battery systems are better installed and managed at a commercial scale. Any system that is hazardous and needs ongoing maintenance is better handled at a commercial level. Electrical utilities or equivalent firms are used to electrical and safety requirements. Furthermore, it is much easier to regulate commercial safety than residential safety. Installing a Powerwall or equivalent outside and within a fireproof enclosure seems reasonable, but I would be cautious about larger storage. I would rather leave fire safety to fire safety professionals.