Creeping Lava Now Threatens Major Hawaiian Power Plant (gizmodo.com)
An anonymous reader quotes a report from Gizmodo: Molten lava from Hawaii's Kilauea volcano has entered the grounds of Puna Geothermal Venture, a geothermal power plant that provides about 25 percent of the Big Island's power. The 38 Megawatt Puna Geothermal Venture (PGV) power plant, which is located in the east rift zone of the Kilauea volcano, was shut down soon after the eruptions began on May 3. Yesterday, lava from Fissure 22 came to within 820 feet (250 meters) of the plant's nearest well pad before stalling, as Reuters reports. Overnight, workers managed to cap the 11th and final well at the facility in anticipation of the lava eventually reaching the facility, and to prevent the uncontrollable release of toxic gases. Mercifully, the lava flow stopped at a ridge near the PGV plant, but as the events of the past two weeks have shown, Mount Kilauea is in an extremely volatile state. The HCCD said Fissure 22 is producing most of the lava feeding the flows, so the situation near the power plant remains precarious.
But that has always worked for Iceland.
You can't directly compare Hawaii and Iceland. Iceland's volcanoes are more "felsic", which means they contain more silicates and are more viscous. So they flow more slowly and this makes them easier to divert by ditching, and cooling with hoses to create walls of solidified lava.
Kilauea in Hawaii is a classic "mafic" volcano. The lava is low in silicates, and less viscous. It flows like water, very rapidly. It also is harder to solidify. Kilauea's lava solidifies into basalt at about 985 C. Iceland's lava will solidify at about 1200 C, and will start to get gooey at even higher temps.
Geothermal has a capacity factor of about 0.7. So the 38 MW the plant is rated for generates on average (38MW)*(0.7) = 26.6 MW.
Solar at Hawaii's location (96704 zip code) has a capacity factor of about 0.124 (this takes into account night, seasons, movement of the sun, weather, maintenance, etc). So generating 26.6 MW would require (26.6 MW)/(0.124) = 215 MW of installed nameplate capacity. That would make it the 18th largest PV solar plant in the U.S.
Assuming you're using commerical 180 W/m^2 panels, this would mean 1.195 million m^2 of solar panels, or 1.195 km^2 of panels alone. Or 67 Panamax-size container ships ( 66 meters x 49 meters) completely covered on PV panels to replace this single geothermal plant.
If you allow space to account for maintenance and tilt to the angle of the sun, the PV solar plants in this capacity range seem to cover about 5-10 km^2. So now you're talking about 280-560 Panamax-sized ships with solar panels on them to replace this single geothermal plant.
Or put another way, a single Panamax-sized ship with every upward-facing surface covered in solar panels would only generate (366 meters)*(49 meters)*(180 W/m^2)*(0.124) = 400287 Watts = 0.4 MW on average at this location. The average U.S. home uses 10,766 kWh per year, or an average of (10766 kWh) / (1 year) = 1481 Watts. So your one ship would be enough to power about 270 homes. There are already 10,000 people evacuated, which if you assume 4 per home is 2500 homes.
People *vastly* overestimate the power density of solar. Mobile solar is stupid unless you can drastically reduce your power consumption. Effective use of solar requires large areas of cheap land.
Um, Why hasn't a concerted effort been made to build a berm uphill from the power plant to divert the lava?
Soon after the eruption started, there was an article that discussed this and the answer is probably that it wouldn't do any good. Lava is more like a wall of rock coming at you than a wave of water. It will push through or over most anything in its way. The amount of work needed to build a berm that would have a suitable enough chance to divert the lava flow is probably not possible in the time given or worth the effort needed.
Much useful information in this article at Hawaii Civil Beat: http://www.civilbeat.org/2018/...
Short quote (there's a lot more at the link):
You joke, but I'm wondering why they couldn't have built it on higher ground.
A big reason is that the upper slopes of Kilauea are inside a national park. Only the lower areas around Pahoa are private land available for commercial development.
Volcanoes National Park