This forum is about wrong numbers in science, politics and the media. It respects good science and good English.
On the issue of whether a Green product investment is better than a 'safe investment', it will depend on the subsidy scheme on offer in a country at a particular time. My understanding is that in the specific case of installing solar panels from around 2010 and maybe for a few years after that in the UK, it did outperform a normal financial investment. These blog posts from a British politician called Roger Helmer in 2010 and 2011 explain the generous subsidy arrangement that was available at the time (I don't know if the subsidy is still available - it sounds as though it was too generous to still be in existence):
Helmer took advantage of the subsidy arrangement and installed a 2.4kV solar panel system at his own house in 2010, even though he was a critic of renewable energy and the subsidy scheme. Subsequently Helmer defected to UKIP (from the Conservative party) in 2012, and became UKIP's energy spokesman, which is a bit strange as UKIP is an anti-renewable energy party but is being represented on energy issues by a spokesman who is making a fair bit of income from having solar panels on his roof.
Another comment I would make Stew is that in situation #2 item 3 "Another $30K of green stuff like battery banks etc.", I don't think the majority of people who install solar panels are interested in battery banks. You would only be interested in spending a substantial amount of money on batteries if you wanted to go off-grid, and you have to be connected to the grid and contributing power to it to get the subsidy (at least in Europe). Also $30K is a bit low to go off-grid using battery storage for most parts of the world.
The "Energy Matters" blog had a recent post where it estimated the cost of battery storage wall units supplied by Tesla to go off-grid at various latitudes.
Assuming a solar power system with battery storage to provide a household consumption of 5000kWh/year, the cost of the battery storage is given as:
At the equator $17.5K. At 20 degrees N latitude $101.5K. At 40 degrees N latitude $238K. At 60 degrees N latitude $535.5K. The total weight of batteries for the latter case is given as 15.3 tons.
By coincidence days I read Ean's debunk of Audi's magic E-diesel project the other day, and then read his Tesla Battery analysis
you've seen this ? by Bloomberg Tesla's New Powerwall Battery Doesn't Work That Well With Solar Musk own company Solar City points out that rather than use a storage battery domestic customers would e better off feeding excess electricity generated back into the grid to claim the generous subsidy.
- However Musk will be angling for laws giving industrial customers big subsidies if they use batteries ..the poor Joe Public will be paying for those subsidies.
Here in Borneo an NGO guy explained to me "It don't understand it out solar battery system on the sunny island here is completely uneconomic and we have to run the diesel generators all nigh to power the fans for sleeping, but in the UK my mother's solar seems to work and she gets paid by the electricity company"
..well yes but the subsidy the UK law forces the energy company to pay her out of everyone else's bills, is so stupidly huge.