Seems likely AWE will not scale to 20 MW anytime soon. Does anyone know of research papers describing how cost of AWE could scale to smaller units, thereby allowing us to estimate the LCOE of many smaller AWE units conpared to a huge VAWT.
If you don’t have papers, I’d also be interested in hearing opinions on the subject.
VAWT:
In the case of wind power , the LCOE of onshore wind turbines ranges between 3.94 and 8.29 €Cent /kWh , making them the second cheapest technology for electricity generation today. This decrease is due to falling plant costs. Offshore wind turbines are significantly more expensive at 7.23 to 12.13 €Cent /kWh , despite the higher annual mean full load hours (FLH) of up to 4500 hours per year. The energy generation costs of offshore wind are higher because of the more costly installation, operating and financing (3000 to 4000 €/kW).
That said the price paid by the user is that of an energy mix. For example, for intermittent renewables a strong fossil back-up is necessary. This is why the LCOE of the energies taken one by one is not necessarily reflected in the bill paid (see the very high cost in Denmark, even if we remove the surplus of taxes, while its electricity is based on a significant part of wind whose LCOE is not high) as shown by the following statistic:
Concerning “many smaller AWE units”, if they are installed permanently, I fear that the LCOE will be even much higher: maintenance multiplied by the number of units, reliability, land use, lifetime, all this if the units can fly more than a few hours, which does not seem to be the case for the crosswind AWES which are still mainly considered. This hypothesis is therefore not realistic, but no worse than the other AWE hypothesis. There are still too much unresolved issues.
Another possibility now is to use “many smaller AWE units” for mobile use, much like Kiwee. I would see a personal use, a bit like covering your roof with solar panels. We send our drone-AWES to store some energy and return home. As we do not know (among other unknowns) the lifespan of an AWES in operation, it is difficult to evaluate the LCOE. This can be a small niche at the best.
This seems more like a business question perhaps. As a buyer I’d be interested in what my initial investment would be and how quickly the investment pays for itself. The seller then has to make an interesting product for me to consider. The only interest I had in the scale would perhaps be that I can’t afford a very big initial investment, as an individual, farmer, or community funded project. It’s also a new product, so I’m only going to invest after I’ve seen plenty of good reviews, which you’ll get quicker from selling many smaller systems.
As some of the components of the system (ground station) will depreciate slower than the others (kites and tethers), to limit my initial risk as a buyer, maybe it’s good for the seller to offer to lease or rent the ground station to me, and to let me buy the kites and so on, and choose different ground station and kite options.
I think the smaller the system, the more you can take advantage of economies of scale and the cheaper everything becomes, and the more potential buyers you have. Perhaps your generator is a tenth the price of a bigger one, there are a hundred potential makers of your smaller kite instead of three, and broken parts can be sent back to you with regular shipping.
You’d need to look at an individual system I think and compare that to grid energy, and the other alternatives like solar and diesel generators that are relevant for your location.
For estimating the cost, I’d perhaps initially only look at the bill of materials, which should stay relatively fixed, and ignore other costs, like labor, as you’re bound to become more efficient and automate things, over time.
And:
The Frauenhofer report is very good. Thanks for finding that. Still, I was thinking some research directed more at what you describe here. Like; if the kite was free [money wise], how small kite wind farms would make sense. Maybe breaking down wiring costs, adding power smoothing costs etc…
We don’t know maintenance and purchase cost of the kites yet, but the other factors should be more well known. If we knew these, that would limit the feasible scale of each kite, at least maybe to a minimum scale.
Eg: A utility scale scale AWE wind farm with 1 kW units probably does not make sense due to extreme wiring costs