Comment by applied_heat | Hacker News Reader

Comment by applied_heat | Hacker News Reader

A constraint for determining project feasibility is the lead time on studies which determine the cost of interconnections. To complete the study the PSS/E or PSLF software is required and the model of the utility’s system, so typically only the utility can complete the study since the models are not available externally and they only have so many people permanently employed performing studies.

The study might show that the upgrades required to inject power at a project location and maintain system stability and reliability are too costly and the project can’t proceed as proposed.

The studies are usually performed in the order that the requests are received.

Project proponents are often unaware of where on the grid the most cost effective interconnections are for a given project size.

The feedback loop between proponents and utility could be tightened up if the utility would publish a map showing available capacity or cost to upgrade vs new capacity for different locations on the grid.

That is one way the utility could meet the demand to perform the studies faster with the same number of quants.

I worry about those interconnections and the risk of cascading failures. I know just enough about it to worry that the problem might be order NP, and a directive to go faster when the modeling, aka software, just can't, could be disastrous. Can someone who knows better reassure me?

More people could perform more studies in parallel but it is a pretty niche skill to be able to perform the studies

The point of the studies is to determine the upgrades required to the transmission system to ensure stability and reliability (prevent cascading failures)

While it is good they are reducing bureaucracy, your point about limited transmission capacity is spot on.

One thing I think is notable. Solar and wind installations performance tends to just degrade instead of going 100% offline like traditional plants. And batteries greatly improve grid reliability. I suspect they can add power to the grid faster than breakers will trip.

Also we're working towards a system where demand can be controlled. Think your electric car stops charging or your air conditioner kicks off for 10 minutes when there is a problem.

Great point, How much battery capacity and energy the utility will require (big expense for project proponent they have to inevitably recover from ratepayers) for solar or wind farms is another Aspect that has to be studied

What I've read and seems to be backed up by how fast utility batteries are being installed is the drop in price of batteries means that suddenly the payback period for batteries is a couple of years.

Batteries exist in a different economic regime than rate payers. Where the price per megawatt varies by 2X or more. Which makes it easier for batteries to make money be arbitrage. As in buy power at 10am for $40/MWH, sell it at 7pm the same day for $80/MWH.

My benchmark for utility scale solar is the installation in Australia that was 100MW and 129MWH and cost about 100 million

So making $40/MWH * 100 MWH/day = $4000 per day * 365 day/yr = 1.4 million revenue per year. Not enough to pay back $100 million.

Like you said The economics of it keep improving though Imp

I think that thing makes money because utilities will pay though the nose for a reserve of instant on demand power.

Right, so then we are back to that cost being recovered from ratepayers.

But they're paying less for that than before. The price power commands depends a lot on how flexible the power source is. Batteries because they provide grid stabilization can charge a premium price.

Reply on news.ycombinator.com