Exhibit 10.6


                         THE BROOKLYN UNION GAS COMPANY
                 d/b/a KEYSPAN ENERGY DELIVERY NEW YORK PROJECT

                           $55,000,000 PROMISSORY NOTE
                                       FOR
                          GAS FACILITIES REVENUE BONDS
                         (THE BROOKLYN UNION GAS COMPANY
         d/b/a KEYSPAN ENERGY DELIVERY NEW YORK PROJECT), 2005 Series B

                               New York, New York
                                November 1, 2005

     FOR VALUE  RECEIVED,  The Brooklyn  Union Gas Company d/b/a KeySpan  Energy
Delivery New York,  formerly known as The Brooklyn Union Gas Company, a New York
corporation (the "Company"),  promises to pay to the order of Citibank, N.A., as
trustee (the "Trustee") under the hereinafter  referred to Indenture,  in lawful
money  of the  United  States,  the  principal  sum of  $55,000,000  (the  "Loan
Amount"),  together with:  (a) interest  thereon at such rate or rates as in the
aggregate will produce an amount equal to the total of all interest becoming due
and  payable  on  $55,000,000  principal  amount  of the New York  State  Energy
Research and Development  Authority's Gas Facilities Revenue Bonds (The Brooklyn
Union Gas Company d/b/a KeySpan Energy  Delivery New York Project),  2005 Series
B, dated as of November 1, 2005 (the "Bonds"),  issued  pursuant to an Indenture
of Trust (the  "Indenture")  dated as of November 1, 2005,  between the New York
State Energy  Research  and  Development  Authority  (the  "Authority")  and the
Trustee;  and (b) such redemption  premiums and other amounts as are required to
be paid by the Company to the Authority as part of the payments  provided in the
Participation  Agreement  dated as of November 1, 2005,  between the Company and
the Authority (the "Participation  Agreement").  The terms and provisions of the
Participation  Agreement  are  incorporated  herein by reference and made a part
hereof.  The foregoing  amounts shall be paid in installments and in the amounts
which shall be due and payable as provided  below.  Except as otherwise  defined
herein, all capitalized words and terms used herein have the same meanings as in
the  Indenture  of Trust  relating  to the Bonds,  dated as of November 1, 2005,
between the Authority and the Trustee.

     The Company shall make Company  Obligation  Payments to the Trustee in such
coin or currency of the United States of America as at the time of payment shall
be legal tender for the payment of public and private  debts.  The Company shall
make payment to the Trustee (i) no later than 12:00 noon (New York City time) on
the Business Day next preceding each Interest Payment Date, for deposit into the
Bond Fund for credit to the  Interest  Account  established  pursuant to Section
10.02 of the  Indenture an  aggregate  amount of funds that will be available on
the next  Business  Day in The City of New York  equal to the  aggregate  amount
required for the payment of the interest  payable on the Auction Rate Bonds,  on
such  Interest  Payment  Date;  and (ii) no later than 12:00 noon (New York City
time) on each Interest  Payment Date,  other than during an Auction Rate Period,
into the Bond Fund for credit to the Interest  Account pursuant to Section 10.02
of the Indenture the amount required for the payment of the interest  payable on
the Outstanding Bonds on such Interest Payment Date.

     In addition,  the Company shall pay an additional amount to the Trustee for
deposit in the Bond Fund and credit to the Principal Account,  Interest Account,


<PAGE>


Redemption  Account  or to be applied to the  payment  of the  principal  of and
premium,  if any, and interest  payable upon  redemption of any Bond pursuant to
Article V of the Indenture.

     The payment  obligations  of the Company under this Company  Obligation (as
defined in the  Indenture)  shall be deemed to be discharged and this note shall
be cancelled in the event that the Bonds shall have been  accelerated  under the
Indenture  and the  Company  shall  have paid or  caused to be paid all  amounts
required  under the  Participation  Agreement to be paid upon the  occurrence of
such acceleration.

     This note shall  finally  mature on June 1, 2025,  except that in the event
the Company should fail to make any of the payments required by this note or the
Participation Agreement to be made to the Authority,  the item or installment so
in default  shall  continue as an  obligation of the Company until the amount in
default shall have been fully paid,  and the Company agrees to pay the same with
interest thereon at the rate of interest borne by the Bonds, to the extent,  but
not exceeding the maximum rate, permitted by law, until paid; provided, however,
that if such failure to pay results in a payment of principal of, or premium, if
any, or interest on the Bonds not being made when due and  payable,  the Company
shall pay the same with interest  thereon,  which interest shall also constitute
an  obligation  of the  Company at the same rate of  interest  per annum as that
payable on the Bonds;  provided,  further, if during an Auction Period Rate such
failure  results in payment of principal of, or premium,  if any, or interest on
Auction Rate Bonds,  not being made when due and payable,  the Company shall pay
the same  with  interest  thereon,  which  interest  shall  also  constitute  an
obligation  of the Company at the Default Rate until paid pursuant to and to the
extent provided in Appendix B of the Indenture.

     The Company  shall not prepay this note or any  portion  thereof  except as
provided in the Participation Agreement and the Indenture.

     If the  Company  should  default  in the  payment  of  any  installment  of
principal of, premium, if any, and interest due under this note or if any one or
more of the events of default  specified in the  Participation  Agreement should
occur, and if any such default is not remedied as provided in the  Participation
Agreement,  the Authority or the Trustee then,  or at any time  thereafter,  may
give  notice to the  Company  declaring  all  unpaid  amounts  of this note then
outstanding,  together  with all  other  unpaid  amounts  outstanding  under the
Participation  Agreement,  to be  immediately  due and payable,  and  thereupon,
without  further  notice  or  demand,  all  such  amounts  shall  become  and be
immediately  due and  payable.  Any  failure to exercise  this option  shall not
constitute  a waiver of the right to exercise  the same at any time in the event
of any continuing or subsequent  default. In the event of default in the payment
of this  note,  the  undersigned  hereby  agrees  to pay all costs  incurred  in
connection  with  the  collection  of the  amounts  then due  hereon,  including
reasonable  attorneys'  fees.  The  payments  hereunder  shall be payable at the
applicable  Principal  Corporate  Trust  Office of the Trustee in New York,  New
York.

     The Company  agrees  that its  obligation  to make the  Company  Obligation
Payments at the times and in the amounts provided in the Company  Obligation and
to make all other payments provided for in the Participation  Agreement shall be
absolute,  irrevocable and unconditional and shall not be subject to any defense


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<PAGE>


(other  than   payment)  or  any  rights  of  setoff,   recoupment,   abatement,
counterclaim  or  deduction  and  without any rights of  suspension,  deferment,
diminution or reduction it might otherwise have against the Authority or Trustee
or the owner of any Bond.

     The Company  hereby  waives  presentment  for payment,  demand,  demand and
protest and notice of protest, demand and dishonor and nonpayment of this note.

     This  note  and all  instruments  securing  the  same  are to be  construed
according to the law of the State of New York.











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<PAGE>



     IN WITNESS  WHEREOF,  the Company has caused this Company  Obligation to be
duly executed and delivered as of November 1, 2005.

                                           THE BROOKLYN UNION GAS COMPANY d/b/a
                                           KEYSPAN ENERGY DELIVERY NEW YORK


(SEAL)
                                           By:_________________________________
ATTEST:

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