Tricky name, in the past the term has always been about kids looking for info on the solar system. I think there is now some element of solar installations there as well but I think it is the minority. The bids looks high and the keyword popular but the advertisers are likely to be seeing a low CTR I suspect. Would guess it is 10% high value searches, 90% junk.
So I guess the question is what would a hyphenated .com.au be worth with 1800 searches & a CPC of $7. I think not a lot but not worthless either. Would say ~$100.