Transcript Sustainable Energy in Denmark Desi Saludes Hillsborough Community College [email protected] In June of 2010, a group of students from HCC traveled to Denmark to examine.

Sustainable Energy
in Denmark
Desi Saludes
Hillsborough Community College
[email protected]
In June of 2010, a group of students from HCC traveled to
Denmark to examine first-hand that country’s energy
strategies.
Denmark is a small country of only 5.9 million people with a
land area of 16,640 km2. It has 7,314 km of coastline. No point
in the country is further than 52 km from the coast.
US/Denmark Comparisons
(2009 Figures)
Population
US
Denmark
309 M
5.7 M
9,158,960 km2
43,075 km2
Annual Energy Use
per capita
99,214 kWHr
42,682 kWHr
Net Energy Imports
27.5%
Area
-17.9%
US/Denmark Comparisons
US
Denmark
Average Gasoline Tax
~$0.46/Gal
~$5.00/Gal
Average Electricity Cost
~$0.09/KWH ~$0.46/KWHR
Maximum Federal Tax Rate
State/Sales/VAT Rates
35%
(>$373,650)
59%
(>$70,000)
up to 10%
25%
US/Denmark Comparisons
US
Installed Wind Capacity 35,000 MW
Wind as % of Total
Electric Production
1.25%
Denmark
3,500 MW
20%
Wind Power
Denmark is perhaps best known for its wind turbines. Wind
power provides over 3500 MW or nearly 21% of all electricity
produced in the country. The US is the world leader in wind
capacity, however, with over 35,000 MW of installed capacity.
Especially in the North of the country, wind turbines are a
ubiquitous sight, both on land and offshore.
Windmill Cooperatives
Special tax exemptions and feed-in tariffs are
designed to encourage private individuals and
groups of individuals to invest in renewable energy.
Typically, several dozen to several hundred
individuals will pool their assets and invest in one or
more wind turbines. The feed-in tariffs guarantee a
fixed price for energy fed into the grid for a period of
time, usually 20 years.
Time until payoff on these investments (when the
turbine is paid off and all additional revenue is free
and clear) is typically 8 – 12 years.
Thermodynamic Efficiency
Conventional power plants are typically about 40%
efficient due to Second Law of Thermodynamics
restrictions. They vent excess heat to the atmosphere or
to local water bodies using cooling towers of cooling
canals. Here in Tampa Bay, the Big Bend power plant
near Apollo Beach becomes a manatee attraction during
the winter due to the warm water ejected by the plant.
This thermal pollution has been suspected of causing
unhealthy changes in the ecosystem of Tampa Bay.
Capturing and using this waste heat can more than
double the efficiency of a power plant to 80% – 90%.
Cooling Towers
Cooling Canals
The Turkey Point Reactor Site has 168 miles of canals.
CHP - Combined Heat and Power
CHP plants use the waste heat from electricity
generation for other purposes, including domestic and
industrial heating. The condensed steam from the power
plant is passed through a heat exchanger, where it gives
off heat to a separate water circuit which is then
distributed through underground pipes to nearby homes
and businesses. In Denmark, 60% of households have
district heating. The Average cost to the consumer per
Btu is approximately 30% of electric or oil heating cost.
The large infrastructure costs for these projects are
largely subsidized by the federal government, using
funds collected via the various energy taxes.
District Heating Pipes - Strudstrupvaerket
This 265 MW coal-fired electric plant provides district heating to
285,000 consumers using over 124 km of hot water distribution
pipes throughout the city of Arhus.
Distribution Pipes
Distribution pipes are insulated and
buried to minimize heat loss along the
transport route.
Home Heating Distribution Pipes
These pipes carry the hot
water from larger pipes
installed underneath the street
into and out of homes and
buildings.
Instruments in each home
measure flow rate,
incoming and outgoing
temperature to calculate
household energy usage.
This small building contains a natural gas fired generator
which produces 1.4 MW of electricity and 2.2 MW of heat for
a small town of 350 homes. The system circulates 40 m3/hr
of water through 4 km of 150 mm pipes.
Here is the generator that provides the power. For
small, rural communities, right-sized units like this
are more efficient than bringing in power and hot
water from a distant plant.
Using Available Resources
Denmark is the world’s leading exporter of pork
products, with 25 million pigs, or about 5 for every
Danish citizen, so there is no shortage of manure.
This pork farmer got together
with two of his fellow farmers and
constructed a small methane
digestion plant. Generous
government subsidies helped
him with the $1.3 Million cost of
the plant.
This small methane-fired generator produces 750
kW of electricity and about one megawatt of heat.
The entire operation is monitored and run by a
single personal computer.
He expects a pay-back time of 8 years. He was so
enthusiastic about his success that he decided to
expand his operation to triple its current size.
Using Available Resources
In forested areas, wood chips from selective thinning
feed the local CHP plants. In barley growing areas,
farmers collect and bale hay to sell to the local CHP
provider. Strict size and water content limits assure a
uniform fuel source.
Energy from Poop and Guts
The Lemvig Biogas facility transforms manure, fish byproducts,
slaughterhouse waste and other agricultural waste into biogas
(75% Methane, 25% CO2) for electricity and district heat serving
14,000 households. The Lemvig facility processes over 90,000
tons of animal manure and nearly 80,000 tons of industrial waste
annually.
Lemvig Biogas Facility
Fermentation Vessels
Biogas Storage Tanks
A small 1.2 MW generator provides all the power to
run the plant and provides district heating for the
citizens of Lemvig.
Electricity from Solid Waste
Most domestic solid waste in Denmark is burned in special
power plants. The garbage is first dumped in a giant pit and
mixed by a crane operator to increase the homogeneity. This
plant burns 41 tons per hour of garbage at full capacity.
The scale of the power plant is impressive. It burns approximately
240,000 tons per year of domestic waste and produces 236,000
MWh of electricity and 500,000 MWh of heat for district heating.
All operations are controlled via a sophisticated network of
computers and sensors which monitor the smokestack and
adjust various parameters to maximize power output and
minimized emissions.
Look familiar? Yes, it’s LabVIEW! (Danish version)
Wave Energy
The Wave Star device in final prototype form. This
2-pad device generates an average of 750 kW.
Wave Energy
The actuator pads are 5 m in diameter.
Wave Energy
The final installed devices will have 20 pads and
generate approximately 10 MW each.
Underground Energy Storage System
The Enopson Company has developed a new heat pump
system that uses underground water in the aquifer as an
energy storage system. During the summer months,
underground water is pumped through heat exchangers and
the warmed water is pumped back underground
Underground Energy Storage System
During the winter, the cycle is reversed and the stored warm
water is pumped back up through the heat exchangers.
Heat is extracted and the cooled water is pumped back into
the cold water reservoir. No net water is added or removed.
Underground Energy Storage System
The system offer a total payback time of under 2 years for
new construction and 3-4 years for retrofitted buildings.
Nordic Folkecenter
The Nordic Folkecenter for Renewable Energy is a think tank
where researchers from all over the world come to work on
designing next-generation renewable energy technologies,
from new oil seeds to optimized turbine blade shapes.
The first hydrogen refueling station in Denmark was
installed for cars that are being tested at the Folkecenter.
Solar panels old and new being tested for
efficiency and aging characteristics.
This dome contains a small scale, closedecosystem, food production facility.
The two swimming pools contain fish that are
harvested to feed the visiting researchers.
Water from the pools is circulated to the balcony
above where vegetables are grown year round.
Here, Preben Maegaard, founder of the Folkecenter
and an internationally respected advocate of
renewable energy technologies, speaks to the
students about his vision for the future.
Recycling
Garbage pickup is very
expensive so most Danes
make regular trips to the
expansive recycling centers.
Appliances, electronics and
building materials are all
accepted and reused.
Bicycles
Bicycles are everywhere in
Denmark. Specially marked
lanes crisscross all major cities.
In Copenhagen, 37% of all
people commute to work by
bicycle.
Parking bicycles is convenient
because nearly all businesses
and government buildings
have ample parking areas
specifically designated for
bicycles.
Public Transit
Like most European countries, Denmark has an extensive
public transit system of buses and rail lines that makes car
ownership optional for most Danes. This bus in Copenhagen
is fueled by biodiesel.
Conclusion
Denmark is a very small country that is culturally, socially
and politically very cohesive and homogeneous. I believe
that the primary lesson to be learned from Denmark’s
approach to energy policy is that regional solutions are
best. In a country like the United States, with our very
wide cultural, social and political heterogeneity, as well
as our vast geographical diversity, solutions to the
energy challenges we face will best be handled on a
regional basis. Where we have wind, build windmills.
Where we have sun, install solar panels. Public transit
will probably have the greatest impact in areas where the
population density is greatest, like on our two coasts.
While we do need a national energy policy that promotes
renewable energy sources, regionally appropriate
technologies will be the key to our success.
Thank you!
Desi Saludes
Hillsborough Community College
[email protected]