Questions and Answers on the 100% Renewable Capitol Bill from SHARE

During recent meetings with state officials, they raised a number of questions regarding the proposal to convert the State Capitol complex buildings to 100% clean renewable energy within the next three years. Below are some of SHARE’s responses.

SHARE is urging the Governor to embrace the effort to convert the Capitol Complex to clean renewable energy and include authorization for that in this year’s budget, both with funding and Article VII language (i.e., including the Renewable Capitol Act, A5633/S2689.)


First, cost information for the recent geothermal conversion of the Michigan Capitol.

Second, will supply chain issues negatively impact the timeline to decarbonize the Capitol Complex?

Third, how to ensure that the Capitol Complex is not receiving its electricity from non-renewable, fossil fuel sources given the status of the New York electricity mix.

Summary of Responses

One very positive fact we just learned is that the Michigan Capitol conversion was far less expensive than we had previously heard. The overall expenditure was $70 million for the entire improvement project, of which geothermal was an important part, but it was apparently only a fraction of the cost. We suspect the figure ($4 million) cited in the news articles we include below is too low, so we are working to confirm the price related to the geothermal conversion. Michigan estimates the payback period to be about 10 years due to the substantial energy savings. (More details below.)

Industry people we spoke to indicated that they do not foresee supply chain issues. We talked to Aztech Geothermal, which has grants from NYSERDA for geothermal district heating projects in Sheridan Hollow and the Mansion and South End neighborhoods. Supply chain considerations are also discussed below.

We certainly agree with the goal of converting the state’s electric supply to 100% carbon-free sources by 2040 (hopefully faster) as laid out in the CLCPA. We do not know why NYPA has been slow in being able to obtain electricity from the proposed solar farm in Oneida; we would appreciate more information on this. The last detailed update we had from NYPA about the proposed solar array was last spring when we were told that the site permitting process was nearing an end. Perhaps it is time to look at bidding out for 100% clean renewable electricity for the Capitol Complex. The 100% Renewable Capitol Act does provide for a power purchase agreement if state-owned renewable energy projects now authorized for NYPA aren’t coming online fast enough. The Act also encourages the state to look into local sources of renewable energy, such as an expansion of the Green Island hydropower facility on the Hudson River, an already designed (but unbuilt) project which could deliver reliable renewable energy into the grid serving the Capital region.

Supply chain issues

According to industry groups such as Aztech Geothermal, there are no supply chain issues that would significantly disrupt the HVAC conversions to the Capital Complex.  The piping, pumps, heat pumps and controls all have multiple competitive sourcing outlets.  COVID supply chain issues from a couple of years ago have actually improved the reliability of supply, since the major heat pump manufacturers have diversified their sources or redesigned to accommodate a broader accessible supply chain. 

Prices for just about everything are higher than a few years ago but supply chain is not a limiting factor for the conversion of the Capital Complex mechanical/HVAC systems to renewable thermal.  

Drilling capacity sometimes gets noted as a limiting factor, but these projects have plenty of lead time and we can certainly get drilling capacity to commit to the phases of the project at the scale needed.  New York has excess geothermal drilling capacity currently, which is a response to the anticipated growth in demand in the coming years. 

Michigan Capitol Conversion to Geothermal 

In its 2017/2018 state budget, the Michigan legislature allocated $70 million toward a Capitol Infrastructure Upgrade (CIU) project. The project, which was funded in part by a tobacco industry settlement, included funding for a ground source geothermal heating and cooling system in addition to other improvements. The 130+ year old Capitol had previously been heated by the Lansing Board of Water & Light’s steam system that runs through parts of downtown Lansing.

With 272 boreholes drilled to a depth of 500 feet, the system is currently the largest geothermal system installed at a U.S. state capitol building. Borehole drilling and installation of piping loops took five months to complete and were installed under the Capitol’s west lawn. The individual loops were tied into a header pipe and then a central manifold pipe that runs to a new underground Central Utility Plant that was added to a former boiler room. The new system went online March 10, 2021.

Prior to the installation of the geothermal system, the Capitol’s annual utility bill was $800,000 per year with $250,000 of the cost associated with the steam heating system. With the 30% reduction in utility costs, the geothermal system is expected to pay for itself in about 10 years. In addition to cost savings, greenhouse gas emissions reduction, and increased comfort for Capitol staff, the new system is also providing much better humidity control, which protects the historic interior of the Capitol, including the dome which was suffering from inadequate airflow using the old system. This short video provides a look at the interior of the Central Utility Plant and a description of the benefits of the geothermal HVAC system.

Some links for Michigan Capitol Project

Michigan Capitol undergoing energy efficiency measures expected to save $250,000 a year

Michigan Capitol Overhaul Includes Geothermal

Michigan’s 138-year-old Capitol is currently undergoing a two-year $70 million upgrade that will include what state officials say will be the largest geothermal system for a state government building in the country. The heating and cooling system will be coupled with other energy efficiency upgrades that aim to cut the Capitol’s $800,000 annual utility bill in half. While it will cost nearly $4 million upfront, officials estimate geothermal will save the state $300,000 a year on heating and cooling costs and pay for itself in roughly a decade.

Capitol Infrastructure Upgrade Report

Inside the Capitol’s new geothermal system and Heritage Hall construction site