NREL
National Renewable Energy Laboratory
https://www.nrel.gov/

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High unit-count AWES Kite Networks easily pencil out to ~100GW scale unit plants. Is this realistic? Single-unit kites have a simple network topology. Many-unit many-connected network topologies are long established in classic kiting and AWE theory, as an obvious scaling path. Based on many historic giant kite cases, unit-kite scaling limits are fairly well understood as operational, ranging to ~1000m2 and ~10MW.  

Simply building an extreme-scale AWE plant to test is not realistic, nor is slow empirical scale-up, given ecological urgency for clean energy. The obvious extreme-scale engineering practice is to simulate extreme-scale plants both numerically, and by subscale prototypes. Heuristic "napkin" calculations suggest dramatic predictions a high fidelity sim should validate. Would aerodynamics operate at extreme scale as expected by mountain-wind interaction observations? Would extreme-scale polymer lattices stay within mass-scaling exponent limits? Would weather modification effects be manageable; benign or even favorable? What would dynamics be across all wind and load conditions? Could the network loiter efficiently during calm by reverse-pumping and gradual sinking? And so on.

NREL, in partnership with other National Labs, intends to continue scaling HAWTS by depending on multi-physics multi-solver simulations preformed on exaflop parallel-processing supercomputer due in 2022. Under NREL's DOE Wind R&D Roadmap mandate to develop AWE, and its general mission to stay abreast of wind engineering-science progress, the simulation of extreme-scale AWES networks should be developed in conjunction with simulation of larger HAWTs. This will also allow extreme-scale AWE to be compared with extreme-scale HAWT farms, so that planners can decide how the choice between these radically different wind technologies compare.

The basic requirements for NREL to integrate AWE into the exaflop computing project are to extend the HAWT wind field model to about 2000m high, and to support the extreme-scale kite networks spring-mass "rag and string" lattice polymer dynamics. These reasonably minor extensions of the intended computation scope, if done now. There would also be a parallel design project to develop AWES virtual models along with the HAWT models. In fact, both the HAWT and AWES sim camps are already working on current generation modeling, and can begin to integrate their work. In AWE there is a particular need to rough-vet a zoo of promising and doomed concepts.

Outdoor subscale model testing of extreme-scale AWES networks will be fast and cheap at ~1/50 scale. Not only would the respective aerodynamics be usefully similar, but many operational and detail-engineering issues could be worked out. A lot could be learned even at wind-tunnel scale. Exploiting the large return-flow plenum of some the world's largest wind tunnels (UMD is a special opportunity). Just as tall buildings are aerodynamically validated in normal wind-tunnel practice, so will new HAWT and AWES designs be early tested. by 2022, the subscale modeling might be at ~1/10 scale, and working well.

Close-correlation of computed sims with subscale modeling is the best possible validation outcome by NREL research, so that extreme-scale AWES platforms can be built, and perhaps be the key game-changer in the historic world transition to 100% clean energy.