Post on 21-May-2022
Conference Title Month DD, YYYY
HILLCREST
CARBON-FREE COST ANALYSIS
April 20, 2021
Conference Title Month DD, YYYY
CODEBuilt to code using typical HVAC systems (gas and electric)
BUSINESS-AS-USUAL Built 10% better than code using typical HVAC systems (gas and electric)
BUNDLE 1AHigh-efficiency buildings with distributed geothermal (all electric)
BUNDLE 1B – ATESHigh-efficiency buildings with district aquifer thermal energy storage (all electric)
BUNDLE 1B – GEOTHERMALHigh-efficiency buildings with district geothermal (all electric)
Energy Scenarios
Image Source: Underground Energy, “ATES Summer Operation – Cooling”
Conference Title Month DD, YYYY
9.0
4.4
1.9
0.4
Prereq.
5 points
10 points
15 points
-
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
Baseline BAU Bundle 1 Bundle 2
ton
s C
O2e
pe
r ca
pit
a*
Wastewater
Solid Waste
Transportation
Natural Gas
Electricity
Hillcrest GHG Emissions Scenarios
*LEED’s definition of per capita includes both resident and working population
Conference Title Month DD, YYYY
• A high-efficiency, all-electric community can
be cost competitive over its life cycle.
• District solutions are viable and should
continue to be developed.
• There is no “clear winner” among the
evaluated scenarios. Their relative cost-
effectiveness will vary based on how
incremental costs are distributed over time.
Key Findings
Conference Title Month DD, YYYY
The following variables are not currently
accounted for:
• Cost of Xcel infrastructure/savings from not
installing natural gas infrastructure
• Operational savings from EV fueling and
maintenance
• Rate structure for on-site solar
• Energy storage costs/savings
Disclaimers
Conference Title Month DD, YYYYIncremental Costs
Incremental Costs vs. Saint Paul Port Authority Business-As-Usual
Bundle 1A Bundle 1B
Residential Energy Efficiency $24-30M $17-$26M
Industrial Energy Efficiency $13-16M $9-$14M
District Energy System n/a $15-21M
Solar $27M $27M
EV Charging $1M $1M
Total $65-74M $69-89M
Incremental costs to achieve
19 LEED points are in the
10s of millions of dollars.
The incremental cost of a
district system may be
comparable to a non-district
system.
Conference Title Month DD, YYYY
Operational Savings vs. Saint Paul Port Authority BAU
Bundle 1A Bundle 1B
Residential Energy Efficiency $17-$30M $14-29M
Industrial Energy Efficiency $11-$20M $10-19M
District Energy System n/a n/a
Solar $36M $36M
EV Charging not quantified not quantified
Total $64-$86M $60-$84M
Operational Savings
Operational savings on utility
bills, O&M, and equipment
replacement over a 25-year
period could offset
incremental costs.
Conference Title Month DD, YYYYUtility Costs – Low-Rise Residential Building (Xcel)
The monthly utility costs for
low-rise residential buildings
are significantly lower than
the business-as-usual
scenario.
* Assumes all savings from efficiency are passed
to residents
** Assumes all savings from efficiency and solar
are passed to residents (doesn’t account for
service fees, etc.)
$154
$132
$96$100
$0$0
$20
$40
$60
$80
$100
$120
$140
$160
$180
Code BAU Bundle 1A* Bundle 1B* Bundle 1A/1B**
Monthly Utility Costs per Unit
Conference Title Month DD, YYYYUtility Costs – Industrial Building (Xcel)
The monthly utility costs for
industrial buildings are
significantly lower than the
business-as-usual scenario.
* Assumes all savings from efficiency are passed
to residents
** Assumes all savings from efficiency and solar
are passed to residents (doesn’t account for
service fees, etc.)
$11,466
$9,661
$5,924 $6,202
$0$0
$2,000
$4,000
$6,000
$8,000
$10,000
$12,000
$14,000
Code BAU Bundle 1A* Bundle 1B* Bundle 1A/1B**
Monthly Utility Costs
Conference Title Month DD, YYYYLife Cycle Costs – Entire Site (Ever-Green Energy)
Life cycle cost analysis can
be used to compare cost-
effectiveness.
Key variables:
• cost of capital
• geothermal well costs $-
$20
$40
$60
$80
$100
$120
$-
$5
$10
$15
$20
$25
$30
$35
$40
BAU Bundle 1A Bundle 1B - ATES Bundle 1B - GEO
30
-Yea
r C
ost
(M
illio
ns)
Firs
t C
ost
an
d N
PV
(M
illio
ns)
Net Present Value First Cost 30-Year Cost
Conference Title Month DD, YYYY
• Port to define key questions to answer and timeline for decision-making.
• Investigate sources to fund incremental costs. Kick-off meeting with Xcel, Ever-Green, and IPS?
• Further develop on-site solar concept. Discuss rate structures with Xcel. Evaluate energy storage options.
• Explore business plan for district system options. Conduct on-site testing to confirm assumptions and refine pricing estimates.
Next steps?