Even with long term contracts in place they will mark the contracts to market so they do notice the loss on their books.

But plants have thermal limits to what they can do, the heat they provide may be used elsewhere, they may provide services to the grid operator... a range of reasons why they'd run even when not profitable for that hour.

In general, plant operators are very good at maximising value (which translates to more revenue for them). And they will happily use all the flexibility at their disposal to do so.

In theory yea, and where possible they will, but a lot of PV installations lack the ability or the incentive to curtail.

Households are usually not exposed to spot price signals, so residential PV will always produce electricity (network permitting).

Utility scale PV up to a few MW may not have the ability, or the operator may not have the option to curtail contracted.

In our country, dynamic pricing is on the raise for consumers and many consumers already profited from these pricing.

COLT, ICML, IJCAI, and AAMAS will all be in Stockholm in July 2018.