Editing Wave power (section)

=== Point absorber buoy ===
This device floats on the surface, held in place by cables connected to the seabed. The point-absorber has a device width much smaller than the incoming wavelength λ. Energy is absorbed by radiating a wave with destructive interference to the incoming waves. Buoys use the swells' rise and fall to generate electricity directly via [[linear alternator|linear generators]],<ref name="Seabased">{{cite web|title=Seabased AB wave energy technology|work=Seabased |url=http://www.seabased.com/en/technology/seabased-wave-energy |access-date=October 10, 2017|archive-url=https://web.archive.org/web/20171010211446/http://www.seabased.com/en/technology/seabased-wave-energy|archive-date=October 10, 2017|url-status=live}}</ref> generators driven by mechanical linear-to-rotary converters,<ref name="PowerBuoy">{{cite web |title=PowerBuoy Technology |publisher=Ocean Power Technologies |url=http://www.oceanpowertechnologies.com/powerbuoy-technology/ |access-date=October 10, 2017|archive-url=https://web.archive.org/web/20171010213214/http://www.oceanpowertechnologies.com/powerbuoy-technology/|archive-date=October 10, 2017|url-status=live}}</ref> or hydraulic pumps.<ref name="CETO">{{cite web|title=Perth Wave Energy Project – Carnegie's CETO Wave Energy technology |url=https://arena.gov.au/projects/perth-wave-energy-project/|access-date=October 10, 2017|archive-url=https://web.archive.org/web/20171011072056/https://arena.gov.au/projects/perth-wave-energy-project/|archive-date=October 11, 2017|url-status=live}}</ref> Energy extracted from waves may affect the shoreline, implying that sites should remain well offshore.<ref name="Tethys">{{cite web|title=Tethys |url=http://tethys.pnnl.gov/technology-type/wave|access-date=April 21, 2014|url-status=live|archive-url=https://web.archive.org/web/20140520003234/http://tethys.pnnl.gov/technology-type/wave|archive-date=May 20, 2014}}</ref>

One point absorber design tested at commercial scale by [[CorPower Ocean|CorPower]] features a negative spring that improves performance and protects the buoy in very large waves. It also has an internal pneumatic cylinder that keeps the buoy at a fixed distance from the seabed regardless of the state of the tide. Under normal operating conditions, the buoy bobs up and down at double the wave amplitude by adjusting the phase of its movements. It rises with a slight delay from the wave, which allows it to extract more energy. The firm claimed a 300% increase (600&nbsp;kW) in power generation compared to a buoy without phase adjustments in tests completed in 2024.<ref>{{Cite web |last=Blain |first=Loz |date=2024-03-07 |title=Video: Wave-amplifying generator bounces twice as high as the swells |url=https://newatlas.com/energy/corpower-wavespring/ |access-date=2024-04-12 |website=New Atlas |language=en-US}}</ref>