For me, in my native/instinctive pattern of thought the problem is efficiency. I've taken to saying that 20% efficiency in PV systems (which is on the whole generous) "chaps my little green heart." But I should admit it is as much my thrifty/cheap heart as my green heart that feels the pangs. But that is just MY personal launching : cheat more from the sun. But there are other perspectives. And they have some important contributions to make.
So let's give them a go...
Among the other, very important, perspectives I have considered over the last two years are those of installers, manufacturers and building owners. They seem natural constituents to keep an eye on, right? But yesterday some other constituencies came to mind: utilities, PPA providers & aggregators. (PPA's, I should add, are Power Purchase Agreements and they have played an important role in the roll out of solar power in the US market.) Those financiers and their machinations are surprisingly important. Even more so in this cash strapped period. ( I understand that I should set aside China in this discussion since, I'm told, they have a much more straightforward finance approach: save and then buy gear to save more.)
But here in the USofA, and elsewhere, the financiers have a place at the table. And a similar place exists for power companies and a new breed of project developers that have moved in to drive the specification/finance and building of PV and wind farms in fields all over the place. But also on roof tops. These independent operators see the opportunity in creating powerplants and inserting them into appropriate places on the grid and they take care of the finance and management issues to capture the accelerated depreciation and then get into contract with the owner of the building that needs the power. Fairly complex but then so are a lot of modern economic arrangements.
But a hybrid, a hot-hybird at least, creates another opportunity: A virtualized power generation company could be created using this technology to diversify the income base. A company of this type could agrigate a bunch of roof-tops in the following way...
Create a PPA with many building owners that sells them Shade, Heat and Air Conditioning Services... creating a mulit-source income stream (in effect, negative rent for the rooftop space/aka solar aperture.) The second income stream comes from selling the electrical production from the whole fleet of arrays. A fleet installed all over an incumbant power distribution utility's service area. The PPA company negotiates this product as a renewable insertion to the power supply (helping to meet renewable goals) and ties to it some sort of dispatchable power source (like a gas plant) to make it perform more like a base supply than a fluctuating renewable supply (and demand a higher, albeit wholesale, price.) As the market evolves, having the watts generated at or near the demand locations may allow for better deals on energy grid transport costs (short grid hops) or conversion to meter-bypassing hookups (to get retail prices.)
What would be a meter-bypassing load? A shop with lots of air power tools could have two compressors (one DC and one AC even) and use the grid AC driven one as a backup. The renewable watts that drive the compressor would never have to touch the grid. Just one private transaction.
Additional streams of income can also come from:
- credit for demand reduction from the HVAC services
- carbon credits etc
- and who knows what else different markets might provide
- roofing service?
A while back, as an exercise, I thought about how a district heat system might work as a way to justify a large-field, utility-style array. Classic inventor-guy fantasy of their product paving acres and acres of land as far as the eye can see... But the relatively low temps and the infrastructure demands did not strike me as an obvious big win (a lovely fantasy but economically a bit dim.) And so I thought I'd have to leave the utility-scale installations to the flat panel PV folks. But now that I can see the role of mediators and aggrigators in the scene, maybe that is not too crazy after all! In the sunbelt, an array that runs efficiently even when the ambient temp is at its worse is worth a good deal all by itself. If it also supplied a small ice business or food processor with chilling and sanitary heat for water, how cool would that be? Plenty cool.
Do you have a thought about how a hot hybrid might be employed? Let me know!