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reyoz | on: Australian energy retailers must offer three hours of free daytime electricity
This is what I am doing. 42 kWh battery, 6 kW solar and fully electrified house, 2x EVs. I am able to charge cars at work and so in the depths of winter I am able to run the house by charging during the 3 hour window. There have been just a couple of cold (~2-4 degC) days when the battery was depleted 1-2 hours before the window starts.

As the weather warms and we get more solar exposure we will easily be in excess. We get a very small export rate with a bonus for no energy consumption during peak evening hours which can offset the fixed daily charge.

There are a lot of gotchas that you need to be aware of. 42 kWh is nominal capacity not the actual usable capacity. House load, max grid import and export capacity, max inverter capacity, AC or DC coupled panels, battery charging profile, battery temp are all factors in how much you can charge in the window. For example I have max 15 kW grid draw, with a 10 kW inverter that can charge the battery. I can put in max ~30 kWh into the battery, so I also run other loads in the house to use the other 5 kW capacity. If I go over 5 kW house load the battery charge is clipped to maintain grid import limit.

throwaway2037 | parent

    > I am able to charge cars at work
Nice perk! Does you know who pays for the electricty? Is this "virtue signalling" by the company or landlord... or a subsidy from the local/state/national gov't? To be clear, I am not making any value judgement about providing free charging for EVs. It seems like good gov't policy to promote the adoption of EVs.
freshpots | root | parent | next
It costs $5-$10 for the electricity to charge a car using level 2 charging. It is a trivial "perk" for an employee that costs an order of magnitude more per hour of work.
pjc50 | root | parent | next
Never mind that, the cost of an urban parking space is considerable.

Here's a £50k London parking space: https://www.rightmove.co.uk/properties/136662200#/?channel=R...

While that's an extreme, I would expect the cost of any urban parking space with a low speed charger to be dominated by the land, then the charger one-off install price, and thereafter electricity use is a pretty trivial cost.

Sydney will also charge you 3,000 $AUS annually for central parking spaces: https://www.revenue.nsw.gov.au/taxes-duties-levies-royalties...

vondur | root | parent | next
Not trivial if they a bunch of chargers. I work for the state in California and we have chargers at work but are charged for them around $.29/kWh which is cheaper than Tesla I think.
ggreer | root | parent
Are they fast DC chargers or level 2 chargers? If it's the former, then that is cheap. If it's latter, then that is some expensive electricity.

I'm in Washington where electricity is cheaper, so 29 cents per kWh is not much cheaper than Tesla's superchargers. The closest one to me is 31 cents in the middle of the day and goes as low as 20 cents per kWh at night. I pay 8 cents per kWh at home, which is where I charge (at much slower speeds) unless I'm on a road trip.

insane_dreamer | root | parent | next
it costs me ~$5 to charge my car overnight at home (level-2) thanks to a residential electricity plan that offers very cheap night/weekend rates in exchange for more expensive rates at peak hours
reyoz | root | parent | next
We have a company fleet which is being slowly converted to EV where possible in line with company net zero policy so there is good charging infrastructure that is extended to all employees. We also have other initiatives such as solar and biogas generation.
bahmboo | root | parent | next
throwaway account and "virtue signalling" plus a dig at so called subsidies. Oh and "no value judgement" except for the value judgement. You are not helpful here.
throwaway2037 | root | parent
Fair point: I work in an industry that checks social media before job offers, so it is not possible to have a public Internal persona. If you look at my profile, you will see that I have been here many here with a modest amount of "Internet points".
sjsdaiuasgdia | root | parent
> Is this "virtue signalling"

> I am not making any value judgement

Calling something "virtue signalling" is a value judgement.

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