Conservation –use less
Transportation –IC engines are inefficient
Passive vs Active
Concentrating Solar Power (CSP) systems, piping and liquid flow
Power Tower (left) with mirrors
Photo voltaic (PV) cells
Solar works at household and community scales
Solar allows for “feed-in tariffs”
The cost of PV cells has dropped significantly
Solar panels require cobalt and other rare earth metals to manufacture
Inconsistent power generation
Large footprint and habitat impact
Difficult to recycle and dispose
Wind turbines currently provide twice the energy solar does
Wind turbines can operate day and night, while solar arrays can only operate during daylight
China now has over 200 GW of installed wind capacity
The U.S. has over 100 GW
Germany has over 60 GW
But this is still only 1/3 of what we produce in hydropower and the turbines are EXPENSIVE
The wind is FREE!
Offshore wind farms (below)
Vertical Axis wind turbines (right)
An extra source of rural income
There is significant potential for wind to supply “all our electricity and global energy needs” (Global Wind Energy Council)
orbital eccentricity: 1000,000 year cycle
variation of tilt: 40,000 year cycle
axial wobble: 26,000 year cycle
axis is wobbling
cirrus clouds
Often produces violent thunderstorms
Advancing warm front air is warmer than the surrounding air
Because warm air is less dense than cool air, the warm front slides up over the cooler air masses
Forms a wide band of cloud formation up to 1,000 km (600 miles) ahead of warmer weather
Often presents with high wispy cirrus clouds a day or two before the front itself arrives
A moist warm front can bring days of drizzle and cloudy skies (London in 1957)
Cold air hugs the ground and pushes warm air up as it advances
Water vapor in the warm air condenses into ice crystals or water droplets
Often produces violent thunderstorms
Narrow band of cloud formation
Warm air in the stratosphere moves ahead of the cold front
Leaves fluffy cumulus clouds after the storm
Cumulonimbus cloud formations (drama)
Residences
Commercial
Industrial
Transportation
Managing overburden removal and disposition
Air emissions are controlled by a variety of technologies and heavily regulated under the Clean Air Act.
What are the contaminants associated with energy generation from coal?
CO2, mercury, arsenic, chromium, lead, uranium, SO2, NOx, particulate
Coal ash (CCR) are usually landfilled or impounded
Fly Ash, a very fine, powdery material composed mostly of silica made from the burning of finely ground coal in a boiler.
Bottom Ash, a coarse, angular ash particle that is too large to be carried up into the smoke stacks so it forms in the bottom of the coal furnace.
Boiler Slag, molten bottom ash from slag tap and cyclone type furnaces that turns into pellets that have a smooth glassy appearance.
Flue Gas Desulfurization Material, a material leftover from the process of reducing sulfur dioxide emissions from a coal-fired boiler.
Air Emissions, including SO2, NOx, CO2, heavy metals (including mercury)
Water Discharged under NPDES Permit, including impacted cooling water and treated water from the combustion process
Waste is often managed on the County level
More than 1 Million tons of waste per year
Combusting the waste to produce energy reduces the waste to ash with 10% of the volume of the parent material.
HERC recovers 11,000 tons of scrap metal annually, more than double the rate collected through curbside recycling
Minnesota has 9 Waste-to-Energy incinerators
North Branch, MN
100 MW facility on 626 acres
Serves 20,000 homes
Xcel Energy's Monticello Nuclear Generating Plant
Permitted to operate until September 8, 2030.
On Feb. 20, 2018, the state of Minnesota settled its lawsuit against the 3M Company in return for a settlement of $850 million.
The Minnesota Pollution Control Agency (MPCA) and Minnesota Department of Natural Resources (DNR) are co-trustees of these funds.
Washington County Landfill Reconstruction
3M contributed $8 million to the $18.5 million cost of reconstruction
Work began with design investigation and design in 2007
Construction was initiated in 2009 and completed in 2012
Solar was installed in 2015
sands/gravel, aggregate mines
most common and mega volume
also Non-metals
much more rare and often more valuable
1- nitrogen fixation
2- nitrification
3- assimilation
4- ammonification
5- denitrification