a lightcell is an engine that uses light to make electricity
(schematic)
hydrogen/fuel
combustion
ultralight power
lightcells burn hydrogen/fuel mixed with sodium illuminant
hot sodium illuminant emits near monochromatic light,
which tuned photovoltaic cells collect to make electricity
sodium illuminant
optical cavity
infrared recycling
⇝
⇝
ceramic recuperator,
heat recycling
3000 suns
yellow light (~2.1eV)
bandgap-tuned
photovoltaic cells (~2.1 eV)
electricity
why
unlock the incredible energy density of hydrogen/fuel
in a highly efficient
whisper quiet package
lightcell can use hydrogen
lightcell can use fuel
natural gas
gasoline
ammonia
butane
propane
alcohols
syngas...
use hydrogen for most cycles
use fuel for extended duration
ideally, synthetic, net zero carbon emissions fuels
how
target efficiency: ≥ 40% wire to wire
power: ≥ 5 kw / kg
energy density: ≫500 watthours/L
module size: ≥ 10kw, < 4 L
hot sodium emits intense,
nearly monochromatic light,
sodium's lone outer shell electron is easily excited
(vid: hacksmith, youtube, 2020)
sodium's weakly bound,
lone outer electron "rings like a bell" at 2.1 eV,
it takes only nanoseconds for the energy absorbed to be reemitted
as 589 nm, 2.1 eV photons when sodium relaxes to its ground state
the transparent reaction cylinder is surrounded by a shell of "hot mirrors", which reflect infrared photons & let visible light through.
this allows for a recycling of waste heat, dramatically increasing efficiency
who
2.1 eV photons can be efficiently absorbed by a photovoltaic cell with a bandgap tuned to 2.1 eV
we can harness the materials developed for solar concentrating multijunction cells
a ceramic, 3d printed counterflow heat exchanger acts as a recuperator, collecting ~90% of the heat from the exhaust, and efficiently preheating intake air and fuel.
its many wiggles form an optical labyrinth, reducing losses from light leaking out the ends more than 20 fold
Physicist (Princeton PPPL)
MIT TR35, Forbes 30u30
Inventor, lightcell
Cofounder, LightSail Energy
"hot mirror" infrared reflector reflectance vs transmission
counterflow ceramic recuperator
Steve Crane, COO
Danielle Fong, CEO
BS. MIT (Geophysics) PhD. UCSD-Scripps
60+ patents in energy
Startup Technical Executive
Cofounder, LightSail Energy
Jon Mapel,
Chief of Development
PhD MIT Electrical Engineering
Serial hardware cofounder in LiDAR, Photovoltaics, LED lighting
Shipped dozens of new products
when
founded: 2022
lightcell is a novel concept engine in development
there's prior art from fields such as concentrated solar, pyrotechnics (fireworks), sodium lamps, and thermophotovoltaics,
however, to our knowledge no past effort brought these concepts together.
this effort harnesses advanced new materials, and uses physics at photon densities rarely explored.
