DC Microgrids with Sol Haroon
Online Live lecture from Thursday, December 20, 2012
DC Microgrid Systems Lecture
On Thursday, Sol Haroon, Lead Systems Engineer at Suniva, gave us a look at what makes a DC microgrid unique and ideal for renewable energy systems. DC is making a comeback in a big way, and if you don’t know how or why, this lecture is a must.
A few questions that were answered:
Are we seeing more manufacturing of DC appliances as DC microgrid systems become more common?
Are the power quality issues created by LED and compact flourescent lights addressed with a DC Microgrid system?
What end-user market is the largest potential in the next few years for DC microgrids? We hear that the DoD bases desire microgrids, but I assume they are AC oriented?
Can we use typical existing house wiring?
How is the DC Voltage regulated?
Also a few shared comments:
This is not the future of smart homes … it is TODAY’s right appraoch.
Companies are now offering DC to DC chargers for phones and laptops.
It’s easier to use DC with solar.
There’s less power loss because there is no inverter.
DC motors are far better with respect to reactance than AC motors.
About 20% of products are now DC and there are huge trasformer losses.
Resources and more:
Here are 2 articles that mention the possibility behind use of microgrid technology to provide power during a utility outage, specifically the recent hurrican Sandy in NY.
Microgrids Keep Power Flowing Through Sandy Outages, November 7, 2012, by Martin LaMonica in MIT Technology Review
Local power generation with microgrids showed the benefits of reliability during Hurricane Sandy.
“The widespread power outages in the wake of Hurricane Sandy cast light on the weakness of a completely centralized electric power system and spotlighted the benefits of distributed power generation.”
How N.Y.U. Stayed (Partly) Warm and Lighted By Matthew L. Wald from NY Times
“When much of Manhattan south of Midtown was blacked out, the lights were on at most of New York University, as was the heat and hot water. As I wrote in January 2011, N.Y.U. installed a small network of its own, burning natural gas in a unit that not only made electricity but also delivered the heat that would otherwise go to waste for use in heating and cooling. That process is known as cogeneration.”
And another great article on Solar Microgrids offering energy in place of kerosene, at a much lower cost, making it possible for more people to have light and of course the other modern necessity- cell phones.
Solar Microgrids by Seema Singh in MIT Technology Review
Village-scale DC grids provide power for lighting and cell phones.
“Each household gets 0.2 amps for seven hours a night—enough to power two LED lights and a mobile-phone charging point—for a prepaid monthly fee of 100 rupees ($2); kerosene and phone charging generally cost 100 to 150 rupees a month.”
The image on the left above is discussed in the lecture- it shows the difference in efficiency between AC ad DC for some common electrical loads.
On the right- a lovely modern DC light ficture that has incredible potential to bring light into an area with an incredibly low energy demand. There was some discussion regarding how many watts were needed to light a room vs. lumens, CFLs vs. LEDs vs. the good ol’ lightbulb we grew up with, and what it takes with AC vs. DC… This can get a little hairy- so here’s an article that might clear this up a bit. The word is, that the new word is- ‘LUMEN’. Read this quick blog:
How Many Lumens Do I Need? from 1000bulbs.com
Are you an Emphatic DC Enthusiast yet?
Emerge AllianceAn open industry association developing standards leading to the rapid adoption of DC power distribution in commercial buildings.
Resources directly from Sol:
Image taken from resource above: Nextek power design guide